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1,462,193 commits

Author SHA1 Message Date
Jakub Kicinski
f994752b11 net: ethtool: optionally skip rtnl_lock on IOCTL path
Convert the IOCTL path similarly to how we converted Netlink.
The device lookup gets a little hairy. We could take rtnl_lock
unconditionally and drop it before calling the driver (this would
avoid the reference + liveness check). But I think being able
to make progress even if rtnl is dead-locked is quite useful.

First extra concern is handling features. List all the cmds which
modify features and always take rtnl_lock. We could fold this list
into ethtool_ioctl_needs_rtnl() but seems cleaner to keep
ethtool_ioctl_needs_rtnl() driver-related. If a driver changed
features and we were not holding rtnl_lock - warn about it.
It can only happen on buggy ops locked drivers (buggy because
they should have set appropriate "I need rtnl for op X" bit).

Second wrinkle is the PHY ID hack which drops the locks while
sleeping. Convert its static "busy" variable which used to
be protected by rtnl_lock to a field in struct ethtool_netdev_state.
This feature is about identifying an adapter or a port within
a system, so being able to blink multiple LEDs at the same
time is likely not very useful in practice. But it's the simplest
fix, we can add a mutex if someone thinks a system should only
be ID'ing one port at a time.

Reviewed-by: Eric Dumazet <edumazet@google.com>
Acked-by: Stanislav Fomichev <sdf@fomichev.me>
Reviewed-by: Jacob Keller <jacob.e.keller@intel.com>
Link: https://patch.msgid.link/20260605002912.3456868-12-kuba@kernel.org
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
2026-06-09 10:13:06 -07:00
Jakub Kicinski
f58a40d07b net: ethtool: ioctl: concentrate the locking
Add another layer of helper functions to make upcoming locking
changes easier. Otherwise we'd need a pretty complex goto
structure. netdev instance lock is now taken slightly sooner
but that should not be an issue since rtnl_lock is already held,
anyway.

Reviewed-by: Eric Dumazet <edumazet@google.com>
Acked-by: Stanislav Fomichev <sdf@fomichev.me>
Reviewed-by: Jacob Keller <jacob.e.keller@intel.com>
Link: https://patch.msgid.link/20260605002912.3456868-11-kuba@kernel.org
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
2026-06-09 10:13:06 -07:00
Jakub Kicinski
732fa5ced1 net: ethtool: optionally skip rtnl_lock in RSS context handlers
Skip rtnl_lock in RSS context handlers if device is ops-locked.
Fairly trivial conversion. bnxt needed rtnl_lock for changing
the main context but looks like additional contexts are fine
without it.

Note (for review bots?) that ethnl_ops_begin() checks whether
the device is still registered.

Reviewed-by: Eric Dumazet <edumazet@google.com>
Acked-by: Stanislav Fomichev <sdf@fomichev.me>
Reviewed-by: Jacob Keller <jacob.e.keller@intel.com>
Link: https://patch.msgid.link/20260605002912.3456868-10-kuba@kernel.org
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
2026-06-09 10:13:05 -07:00
Jakub Kicinski
2526717624 net: ethtool: optionally skip rtnl_lock in ethnl_act_module_fw_flash()
Module firmware flashing reads SFF-8024 identifier bytes via
.get_module_eeprom_by_page(). Other than that it modifies
a bit in the netdev->ethtool struct. Both should be ops-locked
at this point.

Reviewed-by: Eric Dumazet <edumazet@google.com>
Acked-by: Stanislav Fomichev <sdf@fomichev.me>
Reviewed-by: Jacob Keller <jacob.e.keller@intel.com>
Link: https://patch.msgid.link/20260605002912.3456868-9-kuba@kernel.org
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
2026-06-09 10:13:05 -07:00
Jakub Kicinski
0c334c21f5 net: ethtool: optionally skip rtnl_lock in ethnl_tsinfo_dumpit()
ethnl_tsinfo_dumpit() iterates netdevs and per-netdev PHY topology
calling ops->get_ts_info(). Switch to the "ops compat locking"
helpers which take either rtnl_lock or instance lock, depending
on what the device needs.

Reviewed-by: Eric Dumazet <edumazet@google.com>
Acked-by: Stanislav Fomichev <sdf@fomichev.me>
Reviewed-by: Jacob Keller <jacob.e.keller@intel.com>
Link: https://patch.msgid.link/20260605002912.3456868-8-kuba@kernel.org
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
2026-06-09 10:13:05 -07:00
Jakub Kicinski
f16013fde4 net: ethtool: optionally skip rtnl_lock in cable test handlers
Skip rtnl_lock in cable test handlers. This is really a noop since
no ops locked device supports these.

Reviewed-by: Eric Dumazet <edumazet@google.com>
Acked-by: Stanislav Fomichev <sdf@fomichev.me>
Reviewed-by: Jacob Keller <jacob.e.keller@intel.com>
Link: https://patch.msgid.link/20260605002912.3456868-7-kuba@kernel.org
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
2026-06-09 10:13:05 -07:00
Jakub Kicinski
f9a3e05114 net: ethtool: optionally skip rtnl_lock on Netlink path for SET ops
Make ethtool not take rtnl_lock for SET commands when operation
is performed on an ops-locked driver. cfg/cfg_pending are now
ops-locked, since only ethtool modifies them.

Some SET driver callbacks will still need rtnl_lock, most notably
those which may end up calling netdev_update_features() or the qdisc
layer (via netif_set_real_num_tx_queues()). Let drivers selectively
opt back into the rtnl_lock with a new bitfield in ops.

We need two helpers since Netlink and ioctl cmds have different
values. Keep the helpers side by side in common.h to make sure
they get updated together, even tho they will only get called
from ioctl.c and netlink.c.

SET commands which don't use ethnl_default_set_doit() are converted
by subsequent commits.

Reviewed-by: Eric Dumazet <edumazet@google.com>
Acked-by: Stanislav Fomichev <sdf@fomichev.me>
Reviewed-by: Jacob Keller <jacob.e.keller@intel.com>
Link: https://patch.msgid.link/20260605002912.3456868-6-kuba@kernel.org
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
2026-06-09 10:13:05 -07:00
Jakub Kicinski
45079e0013 net: ethtool: optionally skip rtnl_lock on Netlink path for GET ops
ethnl_default_doit() and ethnl_default_dump_one() are both used
exclusively for GET callbacks (former to get info for a single
device or get global strings). ops-locked devices don't need
rtnl_lock for GET callbacks, stop taking it.

Introduce an opt-out mechanism for devices which use phylink (fbnic)
since phylink currently depends on rtnl_lock protection. Subsequent
patches will add more exceptions, anyway. Practically the new helpers
for judging if command needs rtnl_lock could also call
netdev_need_ops_lock() but I find that it makes the code in the callers
slightly less obvious.

Add a helper for IOCTLs already, even tho it's unused so that
we can keep them in sync as the series progresses.

This is the first user-visible step of moving ethtool ops out
from under rtnl. Subsequent patches do the same for SET ops,
as well as the ioctl path.

Reviewed-by: Eric Dumazet <edumazet@google.com>
Acked-by: Stanislav Fomichev <sdf@fomichev.me>
Reviewed-by: Jacob Keller <jacob.e.keller@intel.com>
Link: https://patch.msgid.link/20260605002912.3456868-5-kuba@kernel.org
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
2026-06-09 10:13:04 -07:00
Jakub Kicinski
97f51bf91b net: ethtool: make dev->hwprov ops-protected
dev->hwprov tracks the active hwtstamp provider for the device.
Make it ops protected (instance lock if the netdev driver opts
into holding instance lock around callbacks, otherwise rtnl_lock).

hwprov is written and read in:
 - drivers/net/phy/phy_device.c
    phydev and ops protection don't currently mix, add a comment
 - net/ethtool/
    as of now holds both rtnl lock and ops lock, this one will
    soon only hold one lock or the other

read in:
 - net/core/dev_ioctl.c
    holds both rtnl lock and ops lock
 - net/core/timestamping.c
    RCU reader

The new netdev_ops_lock_dereference() helper does not have
"compat" in the name. The name would be quite long and I think
in this case it should be obvious that we need _a_ lock.
netdev_lock_dereference() already exists and means dev->lock
is always expected.

Reviewed-by: Eric Dumazet <edumazet@google.com>
Acked-by: Stanislav Fomichev <sdf@fomichev.me>
Reviewed-by: Jacob Keller <jacob.e.keller@intel.com>
Link: https://patch.msgid.link/20260605002912.3456868-4-kuba@kernel.org
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
2026-06-09 10:13:04 -07:00
Jakub Kicinski
ded86da4bb net: ethtool: relax ethnl_req_get_phydev() locking assertion
phydev <> netdev linking and lifecycle depends on rtnl_lock.
We want to switch to instance locks for most ethtool ops.
Let's add an assert that ops locked devices don't use phydev
today. If one does we can either opt the phy ops out of
being purely ops locked, or do deeper surgery to make phy
locking ops-compatible. I don't think there's any fundamental
challenge to make that work.

Reviewed-by: Nicolai Buchwitz <nb@tipi-net.de>
Reviewed-by: Maxime Chevallier <maxime.chevallier@bootlin.com>
Reviewed-by: Eric Dumazet <edumazet@google.com>
Acked-by: Stanislav Fomichev <sdf@fomichev.me>
Reviewed-by: Jacob Keller <jacob.e.keller@intel.com>
Link: https://patch.msgid.link/20260605002912.3456868-3-kuba@kernel.org
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
2026-06-09 10:13:04 -07:00
Jakub Kicinski
8845484367 net: ethtool: serialize broadcast notification sequence allocation
ethnl_bcast_seq is a global counter stamped into the nlmsg_seq field
of every multicast notification, allowing userspace to detect dropped
messages. Today the ordering is achieved by using rtnl_lock().

Moving forward we will want ethtool ops to run under just the netdev
instance lock so to establish ordering we need a separate lock
for notifications. With the netdev instance locks operations on
different devices may bypass each other but the expectation is
that it should not matter. What we need to prevent is:
 - notification IDs getting out of order
 - operations on one device getting out of order

For simplicity defer allocating the ID of the notification right
before the notification is delivered. This removes the need for
special handling in ethnl_rss_create_send_ntf().

Reviewed-by: Eric Dumazet <edumazet@google.com>
Acked-by: Stanislav Fomichev <sdf@fomichev.me>
Reviewed-by: Jacob Keller <jacob.e.keller@intel.com>
Link: https://patch.msgid.link/20260605002912.3456868-2-kuba@kernel.org
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
2026-06-09 10:13:04 -07:00
KhaiWenTan
38b7a274cf igc: skip RX timestamp header for frame preemption verification
When RX hardware timestamping is enabled, a 16-byte inline timestamp header
is added to the start of the packet buffer, causing FPE handshake
verification to fail.

Because an incorrect packet buffer is passed to igc_fpe_handle_mpacket(),
the mem_is_zero() check inspects the timestamp metadata instead of the
actual mPacket payload. As a result, valid Verify/Response mPackets can be
missed when inline RX timestamps are present.

Pass pktbuf + pkt_offset to igc_fpe_handle_mpacket() so it inspects the
actual mPacket payload instead of the timestamp header.

Fixes: 5422570c00 ("igc: add support for frame preemption verification")
Co-developed-by: Faizal Rahim <faizal.abdul.rahim@linux.intel.com>
Signed-off-by: Faizal Rahim <faizal.abdul.rahim@linux.intel.com>
Signed-off-by: KhaiWenTan <khai.wen.tan@linux.intel.com>
Reviewed-by: Aleksandr Loktionov <aleksandr.loktionov@intel.com>
Signed-off-by: Tony Nguyen <anthony.l.nguyen@intel.com>
2026-06-09 10:01:07 -07:00
Larysa Zaremba
7bd4355272 ixgbe: do not configure xps for XDP queues
netif_set_xps_queue() should not be called for an XDP Tx queue, since such
queues are not netdev-exposed. On systems with number of CPUs >=64, on E610
adapter, netdev is configured with maximum number queue pairs being 63
(due to MSI-X assignment), but configuring XDP results in 64 XDP queues.

So, during XDP program load, when netif_set_xps_queue() is called for the
last XDP queue, we get a WARNING with a call trace and KASAN report
afterwards (if enabled).

[ 2012.699800] WARNING: net/core/dev.c:2854 at __netif_set_xps_queue+0x116a/0x1e40, CPU#36: xdpsock/103668
[...]
[ 2012.700029] RIP: 0010:__netif_set_xps_queue+0x116a/0x1e40
[ 2012.700035] Code: b6 34 06 48 89 f8 83 e0 07 83 c0 01 40 38 f0 7c 09 40 84 f6 0f 85 03 0a 00 00 0f b7 44 24 40 66 43 89 44 6a 18 e9 01 fb ff ff <0f> 0b e9 f2 ee ff ff 44 8b 44 24 44 45 85 c0 74 50 4d 85 e4 0f 84
[ 2012.700040] RSP: 0018:ffff8882369aeb28 EFLAGS: 00010246
[ 2012.700046] RAX: 0000000000000000 RBX: 000000000000003f RCX: 0000000000000000
[ 2012.700050] RDX: 1ffff1111da3d891 RSI: ffff888120e34250 RDI: ffff8888ed1ec488
[ 2012.700054] RBP: ffff888913281560 R08: 0000000000000000 R09: ffff8888ed1ec000
[ 2012.700058] R10: ffff8888a2e83180 R11: 0000000000000000 R12: 0000000000007fa8
[ 2012.700061] R13: 000000000000003f R14: ffff888120e34854 R15: ffff8889132817c8
[ 2012.700065] FS:  00007fc8ea9ff740(0000) GS:ffff88884cefe000(0000) knlGS:0000000000000000
[ 2012.700069] CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
[ 2012.700073] CR2: 00007f81c8000020 CR3: 00000002299f8006 CR4: 00000000007726f0
[ 2012.700077] PKRU: 55555554
[ 2012.700080] Call Trace:
[ 2012.700084]  <TASK>
[ 2012.700087]  ? ktime_get+0x61/0x150
[ 2012.700097]  ? usleep_range_state+0x133/0x1b0
[ 2012.700108]  ? __pfx_usleep_range_state+0x10/0x10
[ 2012.700114]  netif_set_xps_queue+0x31/0x50
[ 2012.700119]  ixgbe_configure_tx_ring+0x472/0x920 [ixgbe]
[...]
[ 2012.700486]  ixgbe_xdp+0x38f/0x750 [ixgbe]

[...]

[ 2012.701094] BUG: KASAN: slab-out-of-bounds in __netif_set_xps_queue+0x1ac5/0x1e40
[ 2012.701100] Write of size 4 at addr ffff88888d43cff8 by task xdpsock/103668

Skip XPS configuration for XDP Tx queues.

Fixes: 33fdc82f08 ("ixgbe: add support for XDP_TX action")
Reviewed-by: Alexander Lobakin <aleksander.lobakin@intel.com>
Reviewed-by: Aleksandr Loktionov <aleksandr.loktionov@intel.com>
Signed-off-by: Larysa Zaremba <larysa.zaremba@intel.com>
Reviewed-by: Simon Horman <horms@kernel.org>
Tested-by: Patryk Holda <patryk.holda@intel.com>
Signed-off-by: Tony Nguyen <anthony.l.nguyen@intel.com>
2026-06-09 10:01:07 -07:00
Przemyslaw Korba
d1e8f9fd6b idpf: add padding to PTP virtchnl structures
Add padding to virtchnl2 PTP structures to match the Control Plane
expected message sizes:
* virtchnl2_ptp_get_dev_clk_time: 8 -> 16 bytes
* virtchnl2_ptp_set_dev_clk_time: 8 -> 16 bytes
* virtchnl2_ptp_get_cross_time: 16 -> 24 bytes

The FW expects the above sizes and PTP negotiation fails due to the
mismatch. Previously neither the FW nor the driver checked message/reply
sizes strictly, so the problem appeared only after recent validation
improvements.

reproduction steps:
ptp4l -i <pf> -m
Observe: failed to open /dev/ptp0: Permission denied

Fixes: bf27283ba5 ("virtchnl: add PTP virtchnl definitions")
Cc: stable@vger.kernel.org
Reviewed-by: Aleksandr Loktionov <aleksandr.loktionov@intel.com>
Reviewed-by: Alexander Lobakin <aleksander.lobakin@intel.com>
Signed-off-by: Przemyslaw Korba <przemyslaw.korba@intel.com>
Tested-by: Samuel Salin <Samuel.salin@intel.com>
Signed-off-by: Tony Nguyen <anthony.l.nguyen@intel.com>
2026-06-09 10:01:07 -07:00
Manivannan Sadhasivam
f865a57896 PCI: mediatek: Fix IRQ domain leak when port fails to enable
When mtk_pcie_enable_port() fails, mtk_pcie_port_free() removes the port
from pcie->ports and frees the port structure. However, the IRQ domains set
up earlier by mtk_pcie_init_irq_domain() are never freed.

Fix this by refactoring mtk_pcie_irq_teardown() into a per-port helper,
mtk_pcie_irq_teardown_port(), and calling it from mtk_pcie_setup() when
mtk_pcie_enable_port() fails. Since the IRQ teardown must only happen in
the probe error path (during resume, child devices may have active MSI
mappings and the NOIRQ context prohibits sleeping locks),
mtk_pcie_enable_port() is changed to return an error code so callers can
distinguish the two paths and act accordingly.

This issue was reported by Sashiko while reviewing the EcoNet EN7528 SoC
support series.

Fixes: b099631df1 ("PCI: mediatek: Add controller support for MT2712 and MT7622")
Signed-off-by: Manivannan Sadhasivam <manivannan.sadhasivam@oss.qualcomm.com>
Signed-off-by: Manivannan Sadhasivam <mani@kernel.org>
Cc: stable@vger.kernel.org # 5.10
Cc: Caleb James DeLisle <cjd@cjdns.fr>
Link: https://patch.msgid.link/20260521174617.17692-1-mani@kernel.org
2026-06-09 22:19:51 +05:30
Arnd Bergmann
2a185da3ed Microchip ARM64 device tree updates for v7.2
This update includes:
 - the device tree node for the OTP controller on LAN9691 SoC
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Merge tag 'microchip-dt64-7.2' of https://git.kernel.org/pub/scm/linux/kernel/git/at91/linux into soc/dt

Microchip ARM64 device tree updates for v7.2

This update includes:
- the device tree node for the OTP controller on LAN9691 SoC

* tag 'microchip-dt64-7.2' of https://git.kernel.org/pub/scm/linux/kernel/git/at91/linux:
  arm64: dts: microchip: lan969x: add OTP node

Signed-off-by: Arnd Bergmann <arnd@arndb.de>
2026-06-09 18:46:41 +02:00
Arnd Bergmann
cb78caa297 Microchip AT91 device tree updates for v7.2
This update includes:
 - I3C controller device tree node for SAMA7D65 SoC
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Merge tag 'at91-dt-7.2' of https://git.kernel.org/pub/scm/linux/kernel/git/at91/linux into soc/dt

Microchip AT91 device tree updates for v7.2

This update includes:
- I3C controller device tree node for SAMA7D65 SoC

* tag 'at91-dt-7.2' of https://git.kernel.org/pub/scm/linux/kernel/git/at91/linux:
  ARM: dts: microchip: add I3C controller

Signed-off-by: Arnd Bergmann <arnd@arndb.de>
2026-06-09 18:45:33 +02:00
Terry Bowman
c268f949e2 cxl: Fix CXL_HEADERLOG_SIZE to match RAS Capability size
The CXL r4.0 8.2.4.17.7 RAS Capability Structure has total length 0x58
bytes (CXL_RAS_CAPABILITY_LENGTH); the Header Log occupies the trailing
64 bytes at offset 0x18.  CXL_HEADERLOG_SIZE was defined as SZ_512,
eight times the actual on-device size.

header_log_copy() reads CXL_HEADERLOG_SIZE_U32 (128) dwords from the
RAS capability iomap, overrunning the 88-byte mapping by 448 bytes.
The cxl_aer_uncorrectable_error trace event memcpy()s CXL_HEADERLOG_SIZE
(512) bytes from its source.  For the CPER caller the source is
struct cxl_ras_capability_regs::header_log[16] (64 bytes) embedded in a
stack-local cxl_cper_prot_err_work_data, so the memcpy reads 448 bytes
of kernel stack into the trace event ring buffer where userspace can
read it via tracefs.

Set CXL_HEADERLOG_SIZE to 64 and derive CXL_HEADERLOG_SIZE_U32 from it,
bringing all iomap readers into agreement on 16 dwords.  Userspace tools
such as rasdaemon have grown a dependency on the buggy 512-byte (128 u32)
header_log layout in the cxl_aer_uncorrectable_error trace event.  Add
CXL_HEADERLOG_TRACE_SIZE_U32 = 128 and use it for the trace event
__array and its memcpy to preserve that ABI.  Both callers now pass a
zero-filled u32[CXL_HEADERLOG_TRACE_SIZE_U32] staging buffer with only
the first CXL_HEADERLOG_SIZE_U32 (16) entries populated from hardware;
the remaining 112 u32s are zero-padded, keeping the 512-byte trace ring
buffer layout intact.

[ dj: Replaced 64 with SZ_64 per RichardC ]

Fixes: 36f257e3b0 ("acpi/ghes, cxl/pci: Process CXL CPER Protocol Errors")
Fixes: 2905cb5236 ("cxl/pci: Add (hopeful) error handling support")
Cc: stable@vger.kernel.org
Reported-by: Sashiko
Signed-off-by: Terry Bowman <terry.bowman@amd.com>
Reviewed-by: Alison Schofield <alison.schofield@intel.com>
Reviewed-by: Dave Jiang <dave.jiang@intel.com>
Reviewed-by: Ben Cheatham <benjamin.cheatham@amd.com>
Reviewed-by: Richard Cheng <icheng@nvidia.com>
Link: https://patch.msgid.link/20260605180610.2249458-1-terry.bowman@amd.com
Signed-off-by: Dave Jiang <dave.jiang@intel.com>
2026-06-09 09:44:19 -07:00
Arnd Bergmann
2ab5179ebb ARM: dts: OMAP updates for v7.2
Minor DTS fixes & updates
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Merge tag 'omap-for-v7.2/dt-signed' of git://git.kernel.org/pub/scm/linux/kernel/git/khilman/linux-omap into soc/dt

ARM: dts: OMAP updates for v7.2

Minor DTS fixes & updates

* tag 'omap-for-v7.2/dt-signed' of git://git.kernel.org/pub/scm/linux/kernel/git/khilman/linux-omap:
  ARM: dts: dm8168-evm: Set stdout-path to uart3
  arch: arm: dts: cpcap-mapphone: Add audio-codec jack detection interrupts
  arch: arm: dts: cpcap-mapphone: Set VAUDIO regulator always-on
  ARM: dts: ti/omap: omap4-epson-embt2ws: fix typo in iio device property
  ARM: dts: am335x-sl50: Fix audio bitclock and frame master endpoint

Signed-off-by: Arnd Bergmann <arnd@arndb.de>
2026-06-09 18:43:38 +02:00
Wentao Liang
34b9a83c50 nvmet: fix refcount leak in nvmet_sq_create()
In nvmet_sq_create(), a reference on the ctrl is taken
via kref_get_unless_zero() before calling nvmet_check_sqid().
If nvmet_check_sqid() fails, the function returns the error
directly without releasing the reference, leading to a leak.

Fix this by jumping to the "ctrl_put" label, which already
performs the necessary nvmet_ctrl_put(ctrl). This ensures the
reference is properly released on this error path.

Cc: stable@vger.kernel.org
Fixes: 1eb380caf5 ("nvmet: Introduce nvmet_sq_create() and nvmet_cq_create()")
Signed-off-by: Wentao Liang <vulab@iscas.ac.cn>
Signed-off-by: Keith Busch <kbusch@kernel.org>
2026-06-09 09:42:23 -07:00
Arnd Bergmann
c28364c983 mvebu arm for 7.2 (part 1)
Orion5x: Replace machine_is_mss2() with of_machine_is_compatible() in mss2_pci_init()
 
 mvebu_v5_defconfig: Remove stale MACH_LINKSTATION_LSCHL reference
 
 Armada 370: Simplify of_node_put calls and drop redundant NULL checks
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Merge tag 'mvebu-arm-7.2-1' of git://git.kernel.org/pub/scm/linux/kernel/git/gclement/mvebu into soc/arm

mvebu arm for 7.2 (part 1)

Orion5x: Replace machine_is_mss2() with of_machine_is_compatible() in mss2_pci_init()

mvebu_v5_defconfig: Remove stale MACH_LINKSTATION_LSCHL reference

Armada 370: Simplify of_node_put calls and drop redundant NULL checks

* tag 'mvebu-arm-7.2-1' of git://git.kernel.org/pub/scm/linux/kernel/git/gclement/mvebu:
  ARM: orion5x: update board check in mss2_pci_init() to use the DT
  arm: mvebu_v5_defconfig: remove stale MACH_LINKSTATION_LSCHL reference
  ARM: mvebu: simplify of_node_put calls
  ARM: mvebu: drop unnecessary NULL check

Signed-off-by: Arnd Bergmann <arnd@arndb.de>
2026-06-09 18:42:07 +02:00
Shuvam Pandey
4b0dc84b29 PCI: meson: Add missing remove callback
meson_pcie_probe() powers on the PHY and registers the DesignWare host
bridge with dw_pcie_host_init(), but the driver has no remove callback.
On driver unbind or module unload, the driver core therefore proceeds to
devres cleanup without first unregistering the host bridge or powering off
the PHY.

Add a remove callback that deinitializes the DesignWare host bridge and
powers off the PHY while device-managed resources are still valid.

Fixes: 9c0ef6d34f ("PCI: amlogic: Add the Amlogic Meson PCIe controller driver")
Signed-off-by: Shuvam Pandey <shuvampandey1@gmail.com>
Signed-off-by: Manivannan Sadhasivam <mani@kernel.org>
Link: https://patch.msgid.link/1a0c86ab264cdc1c79c917e984b90991af51d827.1779123847.git.shuvampandey1@gmail.com
2026-06-09 22:10:54 +05:30
Ryan Chen
e77bb5dc57
arm64: dts: aspeed: Add initial AST27xx SoC device tree
Add initial device tree support for the ASPEED AST27xx family, the
8th-generation Baseboard Management Controller (BMC) SoCs.

AST27xx SOC Family
 - https://www.aspeedtech.com/server_ast2700/
 - https://www.aspeedtech.com/server_ast2720/
 - https://www.aspeedtech.com/server_ast2750/

The AST27xx features a dual-SoC architecture consisting of two dies,
referred to as SoC0 and SoC1 - interconnected through an internal
proprietary bus. Both SoCs share the same address decoding scheme,
while each maintains independent clock and reset domains.

- SoC0 (CPU die): contains a quad-core Cortex-A35 cluster and two
  Cortex-M4 cores, along with high-speed peripherals.
- SoC1 (I/O die): includes the BootMCU (responsible for system
  boot) and its own clock/reset domains low-speed peripherals.

The device tree describes the SoC0 and SoC1 domains and their peripheral
layouts.

Signed-off-by: Ryan Chen <ryan_chen@aspeedtech.com>
Link: https://lore.kernel.org/r/20260609-upstream_ast2700-v9-3-f631752f0cb1@aspeedtech.com
Signed-off-by: Arnd Bergmann <arnd@arndb.de>
2026-06-09 18:24:42 +02:00
Shuvam Pandey
b12341b98d PCI: meson: Propagate devm_add_action_or_reset() failure
meson_pcie_probe_clock() enables a clock and then registers a devres
action to disable it during teardown. If devm_add_action_or_reset()
fails, it runs the action immediately, disabling the clock.

The return value is currently ignored, so on that failure path,
meson_pcie_probe_clock() returns the disabled clock and probe continues.
Return the error so the existing probe error path unwinds normally.

Fixes: 9c0ef6d34f ("PCI: amlogic: Add the Amlogic Meson PCIe controller driver")
Signed-off-by: Shuvam Pandey <shuvampandey1@gmail.com>
Signed-off-by: Manivannan Sadhasivam <mani@kernel.org>
Reviewed-by: Neil Armstrong <neil.armstrong@linaro.org>
Link: https://patch.msgid.link/177909148011.9588.6639767953842842291@gmail.com
2026-06-09 21:53:56 +05:30
Filipe Manana
ae2eb64bfd btrfs: fix use-after-free after relocation failure with concurrent COW
If we get a failure during relocation, before we update all the extent
buffers that have file extent items pointing to extents from the block
group being relocated, we can trigger a user-after-free on the reloc
control structure (fs_info->reloc_control) if we have a concurrent task
that is COWing a subvolume leaf.

This happens like this:

1) Relocation of data block group X starts;

2) Relocation changes its state to UPDATE_DATA_PTRS;

3) A task doing a rename for example, COWs leaf A from a subvolume tree
   and ends up at btrfs_reloc_cow_block() and extracts fs_info->reloc_ctl
   into a local variable, which then passes to replace_file_extents();

4) The relocation task gets an error and under the label 'out_put_bg' in
   btrfs_relocate_block_group() calls free_reloc_control(), which frees
   the reloc control structure that the rename task is using;

5) The rename task triggers a use-after-free on the reloc control
   structure that was just freed.

Syzbot reported this recently, with the following stack trace:

   [   88.389822][ T5325] BTRFS error (device loop0 state A): Transaction aborted (error -5)
   [   88.389842][ T5325] BTRFS: error (device loop0 state A) in cleanup_transaction:2067: errno=-5 IO failure
   [   88.389864][ T5325] BTRFS info (device loop0 state EA): forced readonly
   [   88.392277][ T5324] BTRFS: error (device loop0 state EA) in btrfs_sync_log:3572: errno=-5 IO failure
   [   88.396630][ T5325] BTRFS info (device loop0 state EA): balance: ended with status: -5
   [   88.400135][ T5346] ==================================================================
   [   88.400148][ T5346] BUG: KASAN: slab-use-after-free in replace_file_extents+0x85f/0x1590
   [   88.400288][ T5346] Read of size 8 at addr ffff888012312010 by task syz.0.0/5346
   [   88.400299][ T5346]
   [   88.400306][ T5346] CPU: 0 UID: 0 PID: 5346 Comm: syz.0.0 Not tainted syzkaller #0 PREEMPT(full)
   [   88.400319][ T5346] Hardware name: QEMU Standard PC (Q35 + ICH9, 2009), BIOS 1.16.3-debian-1.16.3-2 04/01/2014
   [   88.400325][ T5346] Call Trace:
   [   88.400331][ T5346]  <TASK>
   [   88.400336][ T5346]  dump_stack_lvl+0xe8/0x150
   [   88.400351][ T5346]  print_address_description+0x55/0x1e0
   [   88.400364][ T5346]  ? replace_file_extents+0x85f/0x1590
   [   88.400378][ T5346]  print_report+0x58/0x70
   [   88.400389][ T5346]  kasan_report+0x117/0x150
   [   88.400405][ T5346]  ? replace_file_extents+0x85f/0x1590
   [   88.400420][ T5346]  replace_file_extents+0x85f/0x1590
   [   88.400440][ T5346]  ? __pfx_replace_file_extents+0x10/0x10
   [   88.400452][ T5346]  ? update_ref_for_cow+0xa71/0x1270
   [   88.400473][ T5346]  btrfs_force_cow_block+0xa4d/0x2450
   [   88.400492][ T5346]  ? __pfx_btrfs_force_cow_block+0x10/0x10
   [   88.400508][ T5346]  ? __pfx_btrfs_get_32+0x10/0x10
   [   88.400523][ T5346]  btrfs_cow_block+0x3c4/0xa90
   [   88.400542][ T5346]  push_leaf_left+0x2ac/0x4a0
   [   88.400561][ T5346]  split_leaf+0xd16/0x12e0
   [   88.400574][ T5346]  ? btrfs_bin_search+0x924/0xc70
   [   88.400592][ T5346]  ? __pfx_split_leaf+0x10/0x10
   [   88.400602][ T5346]  ? leaf_space_used+0x177/0x1e0
   [   88.400618][ T5346]  ? btrfs_leaf_free_space+0x14a/0x2f0
   [   88.400634][ T5346]  btrfs_search_slot+0x2641/0x2d20
   [   88.400654][ T5346]  ? __pfx_btrfs_search_slot+0x10/0x10
   [   88.400669][ T5346]  ? rcu_is_watching+0x15/0xb0
   [   88.400681][ T5346]  ? trace_kmem_cache_alloc+0x29/0xe0
   [   88.400694][ T5346]  btrfs_insert_empty_items+0x9c/0x190
   [   88.400711][ T5346]  btrfs_insert_inode_ref+0x229/0xcb0
   [   88.400724][ T5346]  ? __pfx_btrfs_insert_inode_ref+0x10/0x10
   [   88.400736][ T5346]  ? __pfx_btrfs_qgroup_convert_reserved_meta+0x10/0x10
   [   88.400751][ T5346]  ? btrfs_record_root_in_trans+0x124/0x180
   [   88.400767][ T5346]  ? start_transaction+0x8a0/0x1820
   [   88.400778][ T5346]  ? btrfs_set_inode_index+0x5e/0x100
   [   88.400787][ T5346]  btrfs_rename2+0x17bb/0x40d0
   [   88.400800][ T5346]  ? check_noncircular+0xda/0x150
   [   88.400814][ T5346]  ? add_lock_to_list+0xc7/0x100
   [   88.400828][ T5346]  ? __pfx_btrfs_rename2+0x10/0x10
   [   88.400842][ T5346]  ? lockdep_hardirqs_on+0x7a/0x110
   [   88.400901][ T5346]  ? lock_acquire+0x221/0x350
   [   88.400915][ T5346]  ? down_write_nested+0x174/0x210
   [   88.400931][ T5346]  ? __pfx_down_write_nested+0x10/0x10
   [   88.400941][ T5346]  ? do_raw_spin_unlock+0x4d/0x210
   [   88.400952][ T5346]  ? try_break_deleg+0x5b/0x180
   [   88.400963][ T5346]  ? __pfx_btrfs_rename2+0x10/0x10
   [   88.400973][ T5346]  vfs_rename+0xa96/0xeb0
   [   88.400992][ T5346]  ? __pfx_vfs_rename+0x10/0x10
   [   88.401010][ T5346]  ovl_fill_super+0x46b7/0x5e20
   [   88.401030][ T5346]  ? __pfx_ovl_fill_super+0x10/0x10
   [   88.401042][ T5346]  ? xas_create+0x1902/0x1b90
   [   88.401060][ T5346]  ? __pfx___mutex_trylock_common+0x10/0x10
   [   88.401076][ T5346]  ? trace_contention_end+0x3d/0x140
   [   88.401094][ T5346]  ? shrinker_register+0x124/0x230
   [   88.401111][ T5346]  ? __mutex_unlock_slowpath+0x1be/0x6f0
   [   88.401127][ T5346]  ? shrinker_register+0x61/0x230
   [   88.401143][ T5346]  ? __pfx___mutex_lock+0x10/0x10
   [   88.401158][ T5346]  ? __pfx___mutex_unlock_slowpath+0x10/0x10
   [   88.401177][ T5346]  ? __raw_spin_lock_init+0x45/0x100
   [   88.401196][ T5346]  ? sget_fc+0x962/0xa40
   [   88.401208][ T5346]  ? __pfx_set_anon_super_fc+0x10/0x10
   [   88.401222][ T5346]  ? __pfx_ovl_fill_super+0x10/0x10
   [   88.401241][ T5346]  get_tree_nodev+0xbb/0x150
   [   88.401257][ T5346]  vfs_get_tree+0x92/0x2a0
   [   88.401272][ T5346]  do_new_mount+0x341/0xd30
   [   88.401283][ T5346]  ? apparmor_capable+0x126/0x170
   [   88.401301][ T5346]  ? __pfx_do_new_mount+0x10/0x10
   [   88.401311][ T5346]  ? ns_capable+0x89/0xe0
   [   88.401322][ T5346]  ? path_mount+0x690/0x10e0
   [   88.401333][ T5346]  ? user_path_at+0xd4/0x160
   [   88.401346][ T5346]  __se_sys_mount+0x31d/0x420
   [   88.401358][ T5346]  ? __pfx___se_sys_mount+0x10/0x10
   [   88.401370][ T5346]  ? __x64_sys_mount+0x20/0xc0
   [   88.401381][ T5346]  ? entry_SYSCALL_64_after_hwframe+0x77/0x7f
   [   88.401391][ T5346]  do_syscall_64+0x15f/0xf80
   [   88.401403][ T5346]  ? trace_irq_disable+0x3b/0x140
   [   88.401413][ T5346]  ? clear_bhb_loop+0x40/0x90
   [   88.401421][ T5346]  entry_SYSCALL_64_after_hwframe+0x77/0x7f
   [   88.401429][ T5346] RIP: 0033:0x7fa1ff79ce59
   [   88.401436][ T5346] Code: ff c3 66 (...)
   [   88.401443][ T5346] RSP: 002b:00007fa2005affe8 EFLAGS: 00000246 ORIG_RAX: 00000000000000a5
   [   88.401456][ T5346] RAX: ffffffffffffffda RBX: 00007fa1ffa16180 RCX: 00007fa1ff79ce59
   [   88.401464][ T5346] RDX: 0000200000000100 RSI: 0000200000002240 RDI: 0000000000000000
   [   88.401474][ T5346] RBP: 00007fa1ff832d6f R08: 0000200000000440 R09: 0000000000000000
   [   88.401481][ T5346] R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000000
   [   88.401488][ T5346] R13: 00007fa1ffa16218 R14: 00007fa1ffa16180 R15: 00007ffc734fba78
   [   88.401500][ T5346]  </TASK>
   [   88.401506][ T5346]
   [   88.401510][ T5346] Allocated by task 5325:
   [   88.401516][ T5346]  kasan_save_track+0x3e/0x80
   [   88.401529][ T5346]  __kasan_kmalloc+0x93/0xb0
   [   88.401542][ T5346]  __kmalloc_cache_noprof+0x31c/0x660
   [   88.401554][ T5346]  btrfs_relocate_block_group+0x217/0xc40
   [   88.401568][ T5346]  btrfs_relocate_chunk+0x115/0x820
   [   88.401577][ T5346]  __btrfs_balance+0x1db0/0x2ae0
   [   88.401587][ T5346]  btrfs_balance+0xaf3/0x11b0
   [   88.401596][ T5346]  btrfs_ioctl_balance+0x3d3/0x610
   [   88.401612][ T5346]  __se_sys_ioctl+0xfc/0x170
   [   88.401626][ T5346]  do_syscall_64+0x15f/0xf80
   [   88.401640][ T5346]  entry_SYSCALL_64_after_hwframe+0x77/0x7f
   [   88.401650][ T5346]
   [   88.401653][ T5346] Freed by task 5325:
   [   88.401659][ T5346]  kasan_save_track+0x3e/0x80
   [   88.401671][ T5346]  kasan_save_free_info+0x46/0x50
   [   88.401680][ T5346]  __kasan_slab_free+0x5c/0x80
   [   88.401692][ T5346]  kfree+0x1c5/0x640
   [   88.401703][ T5346]  btrfs_relocate_block_group+0x95d/0xc40
   [   88.401715][ T5346]  btrfs_relocate_chunk+0x115/0x820
   [   88.401724][ T5346]  __btrfs_balance+0x1db0/0x2ae0
   [   88.401733][ T5346]  btrfs_balance+0xaf3/0x11b0
   [   88.401742][ T5346]  btrfs_ioctl_balance+0x3d3/0x610
   [   88.401757][ T5346]  __se_sys_ioctl+0xfc/0x170
   [   88.401770][ T5346]  do_syscall_64+0x15f/0xf80
   [   88.401785][ T5346]  entry_SYSCALL_64_after_hwframe+0x77/0x7f
   [   88.401795][ T5346]
   [   88.401798][ T5346] The buggy address belongs to the object at ffff888012312000
   [   88.401798][ T5346]  which belongs to the cache kmalloc-2k of size 2048
   [   88.401807][ T5346] The buggy address is located 16 bytes inside of
   [   88.401807][ T5346]  freed 2048-byte region [ffff888012312000, ffff888012312800)
   [   88.401819][ T5346]
   [   88.401822][ T5346] The buggy address belongs to the physical page:
   [   88.401829][ T5346] page: refcount:0 mapcount:0 mapping:0000000000000000 index:0x0 pfn:0x12310
   [   88.401840][ T5346] head: order:3 mapcount:0 entire_mapcount:0 nr_pages_mapped:0 pincount:0
   [   88.401849][ T5346] flags: 0xfff00000000040(head|node=0|zone=1|lastcpupid=0x7ff)
   [   88.401860][ T5346] page_type: f5(slab)
   [   88.401871][ T5346] raw: 00fff00000000040 ffff88801ac42000 dead000000000100 dead000000000122
   [   88.401881][ T5346] raw: 0000000000000000 0000000800080008 00000000f5000000 0000000000000000
   [   88.401892][ T5346] head: 00fff00000000040 ffff88801ac42000 dead000000000100 dead000000000122
   [   88.401902][ T5346] head: 0000000000000000 0000000800080008 00000000f5000000 0000000000000000
   [   88.401913][ T5346] head: 00fff00000000003 fffffffffffffe01 00000000ffffffff 00000000ffffffff
   [   88.401923][ T5346] head: ffffffffffffffff 0000000000000000 00000000ffffffff 0000000000000008
   [   88.401929][ T5346] page dumped because: kasan: bad access detected
   [   88.401935][ T5346] page_owner tracks the page as allocated
   [   88.401941][ T5346] page last allocated via order 3, migratetype Unmovable, gfp_mask 0xd20c0(__GFP_IO|__GFP_FS|__GFP_NOWARN|__GFP_NORETRY|__GFP_COMP|__GFP_NOMEMALLOC), pid 9, tgid 9 (kworker/0:0), ts 83905464494, free_ts 83674944822
   [   88.401961][ T5346]  post_alloc_hook+0x231/0x280
   [   88.401975][ T5346]  get_page_from_freelist+0x24ba/0x2540
   [   88.401990][ T5346]  __alloc_frozen_pages_noprof+0x18d/0x380
   [   88.402004][ T5346]  allocate_slab+0x77/0x660
   [   88.402019][ T5346]  refill_objects+0x339/0x3d0
   [   88.402033][ T5346]  __pcs_replace_empty_main+0x321/0x720
   [   88.402043][ T5346]  __kmalloc_node_track_caller_noprof+0x572/0x7b0
   [   88.402055][ T5346]  __alloc_skb+0x2c1/0x7d0
   [   88.402067][ T5346]  mld_newpack+0x14c/0xc90
   [   88.402080][ T5346]  add_grhead+0x5a/0x2a0
   [   88.402093][ T5346]  add_grec+0x1452/0x1740
   [   88.402105][ T5346]  mld_ifc_work+0x6e6/0xe70
   [   88.402116][ T5346]  process_scheduled_works+0xb5d/0x1860
   [   88.402127][ T5346]  worker_thread+0xa53/0xfc0
   [   88.402138][ T5346]  kthread+0x389/0x470
   [   88.402150][ T5346]  ret_from_fork+0x514/0xb70
   [   88.402161][ T5346] page last free pid 5282 tgid 5282 stack trace:
   [   88.402168][ T5346]  __free_frozen_pages+0xbc7/0xd30
   [   88.402180][ T5346]  __slab_free+0x274/0x2c0
   [   88.402191][ T5346]  qlist_free_all+0x99/0x100
   [   88.402201][ T5346]  kasan_quarantine_reduce+0x148/0x160
   [   88.402211][ T5346]  __kasan_slab_alloc+0x22/0x80
   [   88.402221][ T5346]  __kmalloc_cache_noprof+0x2ba/0x660
   [   88.402231][ T5346]  kernfs_fop_open+0x3f0/0xda0
   [   88.402253][ T5346]  do_dentry_open+0x785/0x14e0
   [   88.402262][ T5346]  vfs_open+0x3b/0x340
   [   88.402270][ T5346]  path_openat+0x2e08/0x3860
   [   88.402281][ T5346]  do_file_open+0x23e/0x4a0
   [   88.402292][ T5346]  do_sys_openat2+0x113/0x200
   [   88.402300][ T5346]  __x64_sys_openat+0x138/0x170
   [   88.402309][ T5346]  do_syscall_64+0x15f/0xf80
   [   88.402326][ T5346]  entry_SYSCALL_64_after_hwframe+0x77/0x7f
   [   88.402336][ T5346]
   [   88.402339][ T5346] Memory state around the buggy address:
   [   88.402345][ T5346]  ffff888012311f00: fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc
   [   88.402352][ T5346]  ffff888012311f80: fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc
   [   88.402359][ T5346] >ffff888012312000: fa fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb
   [   88.402365][ T5346]                          ^
   [   88.402370][ T5346]  ffff888012312080: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb
   [   88.402380][ T5346]  ffff888012312100: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb
   [   88.402385][ T5346] ==================================================================

Fix this by:

1) Making the reloc control structure ref counted;

2) Make revery place that access fs_info->reloc_ctl outside the relocation
   code, which at the moment it's only replace_file_extents() and
   btrfs_init_reloc_root(), get a reference count on the structure.
   There's also btrfs_update_reloc_root() that is called outside the
   relocation code, but this case is safe because it's only called in
   the transaction commit path while under the fs_info->reloc_mutex
   protection, but nevertheless grab a reference to make the code more
   consistent and avoid false alerts from AI reviews;

3) Add a spinlock to protect fs_info->reloc_ctl, since we can not take the
   fs_info->reloc_mutex as that would cause a deadlock since that lock is
   taken in the transaction commit path. That spinlock is taken before
   setting fs_info->reloc_ctl to an allocated structure, setting it to
   NULL and reading fs_info->reloc_ctl;

4) Make sure the structure is freed only when its reference count drops to
   zero.

Reported-by: syzbot+0eea49bba18051dea35e@syzkaller.appspotmail.com
Link: https://lore.kernel.org/linux-btrfs/6a1df323.bb0696ed.125a22.000a.GAE@google.com/
Reviewed-by: Qu Wenruo <wqu@suse.com>
Signed-off-by: Filipe Manana <fdmanana@suse.com>
Signed-off-by: David Sterba <dsterba@suse.com>
2026-06-09 18:22:47 +02:00
Filipe Manana
50c134f2a9 btrfs: move WARN_ON on unexpected error in __add_tree_block()
There's no point in having the WARN_ON(1) inside the if statement for the
unexpected error. Move it into the if statement's condition, which brings
a couple benefits:

1) It marks the branch as unlikely, hinting the compiler to generate
   better code;

2) The WARN_ON() produces a stack trace after the dumped leaf and error
   message which can hide that more important information in case we get
   a truncated dmesg/syslog.

Reviewed-by: Qu Wenruo <wqu@suse.com>
Signed-off-by: Filipe Manana <fdmanana@suse.com>
Signed-off-by: David Sterba <dsterba@suse.com>
2026-06-09 18:22:47 +02:00
Filipe Manana
f51228e1ba btrfs: move locking into btrfs_get_reloc_bg_bytenr()
It does not make sense for the single caller to have the responsability
to lock the relocation mutex before calling the function and then have
the function to assert the lock is held. As this is a function in
relocation.c, move the locking details into it.

Reviewed-by: Qu Wenruo <wqu@suse.com>
Signed-off-by: Filipe Manana <fdmanana@suse.com>
Signed-off-by: David Sterba <dsterba@suse.com>
2026-06-09 18:22:47 +02:00
Weiming Shi
b0d27d4379 btrfs: lzo: reject compressed segment that overflows the compressed input
lzo_decompress_bio() validates each on-disk segment length seg_len only
against the workspace cbuf size, not against the compressed input size
(compressed_len, the total folio bytes of the bio).  A crafted extent can
carry a segment whose seg_len passes the cbuf check but runs past the end
of the bio, so copy_compressed_segment() walks off the last folio:
get_current_folio() then returns the NULL folio from bio_next_folio(), and
with CONFIG_BTRFS_ASSERT disabled (default) folio_size(NULL) faults.

 BUG: KASAN: null-ptr-deref in lzo_decompress_bio (fs/btrfs/lzo.c:383)
 Read of size 8 at addr 0000000000000000 by task kworker/u8:1/29
 Workqueue: btrfs-endio simple_end_io_work
  kasan_report (mm/kasan/report.c:590)
  lzo_decompress_bio (fs/btrfs/lzo.c:383)
  end_bbio_compressed_read (fs/btrfs/compression.c:1065)
  btrfs_bio_end_io (fs/btrfs/bio.c:135)
  btrfs_check_read_bio (fs/btrfs/bio.c:180 fs/btrfs/bio.c:285)
  simple_end_io_work
  process_one_work
  worker_thread

Reject any segment whose payload would extend beyond compressed_len before
copying it, treating it as corruption like the other on-disk validation
failures in this function.

Reported-by: Xiang Mei <xmei5@asu.edu>
Fixes: a6e66e6f8c ("btrfs: rework lzo_decompress_bio() to make it subpage compatible")
Assisted-by: Claude:claude-opus-4-8
Reviewed-by: Qu Wenruo <wqu@suse.com>
Signed-off-by: Weiming Shi <bestswngs@gmail.com>
Signed-off-by: David Sterba <dsterba@suse.com>
2026-06-09 18:22:46 +02:00
Qu Wenruo
acf9ed3a6c btrfs: retry faulting in the pages after a zero sized short direct write
Currently btrfs_direct_write() will not try to fault in the pages, but
directly fall back to buffered writes, if the first page of the buffer
can not be faulted in.

For example, during generic/362 with nodatasum mount option, there is a
write at file offset 0, length PAGE_SIZE, and the page is not faulted in.
Then we go the following callchain and directly fall back to buffered
IO:

 btrfs_direct_write()
 |- btrfs_dio_write()
 |-  __iomap_dio_rw()
 |  |- iomap_iter()
 |  |  |- btrfs_dio_iomap_begin()
 |  |     Now an ordered extent is allocated for the 4K write.
 |  |
 |  |- iomi.status = iomap_dio_iter()
 |  |  Where iomap_dio_iter() returned -EFAULT.
 |  |
 |  |- ret = iomap_iter()
 |  |  |- btrfs_dio_iomap_end()
 |  |  |  | return -ENOTBLK
 |  |  |- return -ENOTBLK
 |  |- if (ret == -ENOTBLK) { ret = 0; }
 |     Now the return value is reset to 0.
 |
 |- ret = iomap_dio_complete()
 |  Since no byte is submitted, @ret is now zero.
 |
 |- if (iov_iter_count() > 0 && (ret == -EFAULT || ret > 0))
 |  @ret is zero, thus not meeting the above retry condition
 |
 |- Fallback to buffered

Just slightly loosen the condition to allow retry faulting in pages after
a zero sized short write.

Unlike the previous two bug fixes, this one is not really cause any real
bug, but only reducing the chance to do zero-copy direct IO.
Thus it doesn't really require stable-CC nor fixes-tag.

Reviewed-by: Boris Burkov <boris@bur.io>
Signed-off-by: Qu Wenruo <wqu@suse.com>
Signed-off-by: David Sterba <dsterba@suse.com>
2026-06-09 18:22:46 +02:00
Qu Wenruo
ff66fe6662 btrfs: fix incorrect buffered IO fallback for append direct writes
[BUG]
With the previous bug of short direct writes fixed, test case
generic/362 (*) still fails with the following error with nodatasum
mount option:

 generic/362  0s ... - output mismatch (see /home/adam/xfstests/results//generic/362.out.bad)
 - output mismatch (see /home/adam/xfstests/results//generic/362.out.bad)
    --- tests/generic/362.out	2024-08-24 15:31:37.200000000 +0930
    +++ /home/adam/xfstests/results//generic/362.out.bad	2026-05-27 10:13:09.072485767 +0930
    @@ -1,2 +1,3 @@
     QA output created by 362
    +Wrong file size after first write, got 8192 expected 4096
     Silence is golden
    ...

*: If the test case has been executed before with default data checksum,
the failure will not reproduce. Need the following fix to make it
reliably reproducible:
https://lore.kernel.org/linux-btrfs/20260528111659.87113-1-wqu@suse.com/

[CAUSE]
Inside btrfs_dio_iomap_begin() for a direct write, we increase the isize
if it's beyond the current isize.

But if the direct io finished short, we do not revert the isize to the
previous value nor to the short write end.

Then if we need to fall back to buffered writes, and the write has
IOCB_APPEND flag, then the buffered write will be positioned at the
incorrect isize.

The call chain looks like this:

 btrfs_direct_write(pos=0, length=4K)
 |- __iomap_dio_rw()
 |  |- iomap_iter()
 |  |  |- btrfs_dio_iomap_begin()
 |  |     |- btrfs_get_blocks_direct_write()
 |  |        |- i_size_write()
 |  |           Which updates the isize to the write end (4K).
 |  |
 |  |- iomap_dio_iter()
 |  |  Failed with -EFAULT on the first page.
 |  |
 |  |- iomap_iter()
 |  |  |- btrfs_dio_iomap_end()
 |  |     Detects a short write, return -ENOTBLK
 |  |- if (ret == -ENOTBLK) { ret = 0;}
 |     Which resets the return value.
 |
 |- ret = iomap_dio_complet()
 |  Which returns 0.
 |
 |- btrfs_buffered_write(iocb, from);
    |- generic_write_checks()
       |- iocb->ki_pos = i_size_read()
          Which is still the new size (4K), other than the original
	  isize 0.

[FIX]
Introduce the following btrfs_dio_data members:

- old_isize

- updated_isize
  If the direct write has enlarged the isize.

Then if we got a short write, and btrfs_dio_data::updated_isize is set,
revert to the correct isize based on old_isize and current file
position.

And here we call i_size_write() without holding an extent lock, which is
a very special case that we're safe to do:

 - Only a single writer can be enlarging isize
   Enlarging isize will take the exclusive inode lock.

 - Buffered readers need to wait for the OE we're holding
   Buffered readers will lock extent and wait for OE of the folio range.
   Sometimes we can skip the OE wait, but since all page cache is
   invalidated, the OE wait can not be skipped.

But I do not think this is the most elegant solution, nor covers all
cases. E.g. if the bio is submitted but IO failed, we are unable to do
the revert.

I believe the more elegant one would be extend the EXTENT_DIO_LOCKED
lifespan for direct writes, so that we can update the isize when a
write beyond EOF finished successfully.

However that change is too huge for a small bug fix.
So only implement the minimal partial fix for now.

[REASON FOR NO FIXES TAG]
The bug is again very old, before commit f85781fb50 ("btrfs: switch to
iomap for direct IO") we are already increasing isize without a
proper rollback for short writes.

Thus only a CC to stable.

CC: stable@vger.kernel.org # 5.15+
Reviewed-by: Boris Burkov <boris@bur.io>
Signed-off-by: Qu Wenruo <wqu@suse.com>
Signed-off-by: David Sterba <dsterba@suse.com>
2026-06-09 18:22:46 +02:00
Qu Wenruo
66ff4d366e btrfs: fix false IO failure after falling back to buffered write
[BUG]
The test case generic/362 will fail with "nodatasum" mount option (*):

 MOUNT_OPTIONS -- -o nodatasum /dev/mapper/test-scratch1 /mnt/scratch

 generic/362  0s ... - output mismatch (see /home/adam/xfstests/results//generic/362.out.bad)
    --- tests/generic/362.out	2024-08-24 15:31:37.200000000 +0930
    +++ /home/adam/xfstests/results//generic/362.out.bad	2026-05-27 10:21:17.574771567 +0930
    @@ -1,2 +1,3 @@
     QA output created by 362
    +First write failed: Input/output error
     Silence is golden
    ...

*: If the test case has been executed before with default data checksum,
the failure will not reproduce. Need the following fix to make it
reliably reproducible:
https://lore.kernel.org/linux-btrfs/20260528111659.87113-1-wqu@suse.com/

[CAUSE]
Inside __iomap_dio_rw(), the -EFAULT/-ENOTBLK error is not directly returned.
Thus we never got an error pointer from __iomap_dio_rw().

The call chain looks like this:

 btrfs_direct_write()
 |- btrfs_dio_write()
 |-  __iomap_dio_rw()
 |  |- iomap_iter()
 |  |  |- btrfs_dio_iomap_begin()
 |  |     Now an ordered extent is allocated for the 4K write.
 |  |
 |  |- iomi.status = iomap_dio_iter()
 |  |  Where iomap_dio_iter() returned -EFAULT.
 |  |
 |  |- ret = iomap_iter()
 |  |  |- btrfs_dio_iomap_end()
 |  |  |  |- btrfs_finish_ordered_extent(uptodate = false)
 |  |  |  |  |- can_finish_ordered_extent()
 |  |  |  |     |- btrfs_mark_ordered_extent_error()
 |  |  |  |        |- mapping_set_error()
 |  |  |  |           Now the address space is marked error.
 |  |  |  | return -ENOTBLK
 |  |  |- return -ENOTBLK
 |  |- if (ret == -ENOTBLK) { ret = 0; }
 |     Now the return value is reset to 0.
 |     Thus no error pointer will be returned.
 |
 |- ret = iomap_dio_complete()
 |  Since no byte is submitted, @ret is 0.
 |
 |- Fallback to buffered IO
 |  And the buffered write finished without error
 |
 |- filemap_fdatawait_range()
    |- filemap_check_errors()
       The previous error is recorded, thus an error is returned

However the buffered write is properly submitted and finished, the error
is from the btrfs_finish_ordered_extent() call with @uptodate = false.

[FIX]
When a short dio write happened, any range that is submitted will have
btrfs_extract_ordered_extent() to be called, thus the submitted range
will always have an OE just covering the submitted range.

The remaining OE range is never submitted, thus they should be treated
as truncated, not an error. So that we can properly reclaim and not
insert an unnecessary file extent item, without marking the mapping as
error.

Extract a helper, btrfs_mark_ordered_extent_truncated(), and utilize
that helper to mark the direct IO ordered extent as truncated, so it
won't cause failure for the later buffered fallback.

[REASON FOR NO FIXES TAG]
The bug itself is pretty old, at commit f85781fb50 ("btrfs: switch to
iomap for direct IO") we're already passing @uptodate=false finishing
the OE.
But at that time OE with IOERR won't call mapping_set_error(), so it's
not exposed.
Later commit d61bec08b9 ("btrfs: mark ordered extent and inode with
error if we fail to finish") finally exposed the bug, but that commit
is doing a correct job, not the root cause.

Anyway the bug is very old, dating back to 5.1x days, thus only CC to
stable.

CC: stable@vger.kernel.org # 5.15+
Reviewed-by: Boris Burkov <boris@bur.io>
Signed-off-by: Qu Wenruo <wqu@suse.com>
Signed-off-by: David Sterba <dsterba@suse.com>
2026-06-09 18:22:46 +02:00
Filipe Manana
c4e7778580 btrfs: use verbose assertions in backref.c
While debugging a relocation issue I hit an assertion in backref.c but it
was not super useful, since it could not tell what was the unexpected
value that triggered the assertion. The stack trace was this:

  [583246.338097] assertion failed: !cache->nr_nodes, in fs/btrfs/backref.c:3158
  [583246.339588] ------------[ cut here ]------------
  [583246.340573] kernel BUG at fs/btrfs/backref.c:3158!
  [583246.342075] Oops: invalid opcode: 0000 [#1] SMP PTI
  [583246.343294] CPU: 5 UID: 0 PID: 677957 Comm: btrfs Not tainted 7.1.0-rc4-btrfs-next-234+ #1 PREEMPT(full)
  [583246.345715] Hardware name: QEMU Standard PC (i440FX + PIIX, 1996), BIOS rel-1.16.2-0-gea1b7a073390-prebuilt.qemu.org 04/01/2014
  [583246.348694] RIP: 0010:btrfs_backref_release_cache.cold+0x61/0x84 [btrfs]
  [583246.350759] Code: 90 d5 7c (...)
  [583246.354923] RSP: 0018:ffffd4fc88c93ad8 EFLAGS: 00010246
  [583246.355982] RAX: 000000000000003e RBX: ffff8dec90d97020 RCX: 0000000000000000
  [583246.357459] RDX: 0000000000000000 RSI: 0000000000000001 RDI: 00000000ffffffff
  [583246.359517] RBP: ffff8dec8eeb78c0 R08: 0000000000000000 R09: 3fffffffffefffff
  [583246.361180] R10: ffffd4fc88c93970 R11: 0000000000000003 R12: ffff8decd21f3470
  [583246.363184] R13: 00000000fffffffe R14: ffff8decd21f3000 R15: ffff8decd21f3000
  [583246.364666] FS:  00007f9a51751400(0000) GS:ffff8df3f4255000(0000) knlGS:0000000000000000
  [583246.366287] CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
  [583246.367443] CR2: 00007f9a518ed8f5 CR3: 00000004467c8002 CR4: 0000000000370ef0
  [583246.368969] Call Trace:
  [583246.369541]  <TASK>
  [583246.370040]  relocate_block_group+0xf2/0x520 [btrfs]
  [583246.371243]  btrfs_relocate_block_group+0x9a9/0x22e0 [btrfs]
  [583246.372443]  ? preempt_count_add+0x47/0xa0
  [583247.532978]  ? btrfs_tree_read_lock_nested+0x19/0x90 [btrfs]
  [583247.534520]  ? mutex_lock+0x1a/0x40
  [583247.602233]  ? btrfs_scrub_pause+0x2e/0x120 [btrfs]
  [583247.603543]  btrfs_relocate_chunk+0x3b/0x1a0 [btrfs]
  [583247.604893]  btrfs_balance+0x9d5/0x1920 [btrfs]
  [583247.606189]  ? preempt_count_add+0x69/0xa0
  [583247.607030]  btrfs_ioctl+0x260c/0x2a20 [btrfs]
  [583247.608015]  ? __memcg_slab_free_hook+0x156/0x1a0
  [583247.636971]  __x64_sys_ioctl+0x92/0xe0
  [583247.679247]  do_syscall_64+0x60/0xf20
  [583247.753297]  ? clear_bhb_loop+0x60/0xb0
  [583247.756321]  entry_SYSCALL_64_after_hwframe+0x76/0x7e
  [583247.787018] RIP: 0033:0x7f9a5186a8db
  [583247.787787] Code: 00 48 89 (...)
  [583247.791410] RSP: 002b:00007fff2ffa6ac0 EFLAGS: 00000246 ORIG_RAX: 0000000000000010
  [583247.792897] RAX: ffffffffffffffda RBX: 0000000000000003 RCX: 00007f9a5186a8db
  [583247.794319] RDX: 00007fff2ffa6bb0 RSI: 00000000c4009420 RDI: 0000000000000003
  [583247.795714] RBP: 0000000000000000 R08: 0000000000000000 R09: 0000000000000000
  [583247.797149] R10: 0000000000000000 R11: 0000000000000246 R12: 00007fff2ffa903f
  [583247.798685] R13: 00007fff2ffa6bb0 R14: 0000000000000002 R15: 0000000000000002
  [583247.800136]  </TASK>

So update all simple assertions in backref.c to print out the values when
they aren't testing simple boolean conditions.

Reviewed-by: Qu Wenruo <wqu@suse.com>
Signed-off-by: Filipe Manana <fdmanana@suse.com>
Signed-off-by: David Sterba <dsterba@suse.com>
2026-06-09 18:22:46 +02:00
Qu Wenruo
7af30ba6eb btrfs: print a message when a missing device re-appears
There is a bug report that fstrim crashed, and that crash is eventually
pinned down to a missing device which re-appeared and screwed up callers
that only checks BTRFS_DEV_STATE_MISSING, but not
BTRFS_DEV_STATE_WRITEABLE nor device->bdev.

A missing device re-appearing can be very tricky, as for now it will
result in a device without WRITEABLE or MISSING flag, and still no bdev
pointer.

As the first step to enhance handling of such re-appearing missing
devices, add a dmesg output when a missing device re-appeared.

Reviewed-by: Filipe Manana <fdmanana@suse.com>
Signed-off-by: Qu Wenruo <wqu@suse.com>
Signed-off-by: David Sterba <dsterba@suse.com>
2026-06-09 18:22:46 +02:00
Qu Wenruo
1b1937eb08 btrfs: do not trim a device which is not writeable
[BUG]
There is a bug report that btrfs/242 can randomly fail with the
following NULL pointer dereference:

  run fstests btrfs/242 at 2026-06-01 10:25:08
  BTRFS: device fsid d4d7f234-487c-4787-88e4-47a8b68c9874 devid 1 transid 9 /dev/sdc (8:32) scanned by mount (122609)
  BTRFS info (device sdc): first mount of filesystem d4d7f234-487c-4787-88e4-47a8b68c9874
  BTRFS info (device sdc): using crc32c checksum algorithm
  BTRFS warning (device sdc): devid 2 uuid fbe72d72-3272-482d-80fb-ab88ed398192 is missing
  BTRFS warning (device sdc): devid 2 uuid fbe72d72-3272-482d-80fb-ab88ed398192 is missing
  BTRFS info (device sdc): allowing degraded mounts
  BTRFS info (device sdc): turning on async discard
  BTRFS info (device sdc): enabling free space tree
  Unable to handle kernel NULL pointer dereference at virtual address 0000000000000018
  user pgtable: 4k pages, 48-bit VAs, pgdp=000000013fd6b000
  CPU: 4 UID: 0 PID: 122625 Comm: fstrim Not tainted 7.0.10-2-default #1 PREEMPT(full) openSUSE Tumbleweed e9a5f6b24978fba3bf015a992f865837fdfff3dd
  Hardware name: QEMU KVM Virtual Machine, BIOS edk2-20250812-19.fc42 08/12/2025
  pstate: 01400005 (nzcv daif +PAN -UAO -TCO +DIT -SSBS BTYPE=--)
  pc : btrfs_trim_fs+0x34c/0xa00 [btrfs]
  lr : btrfs_trim_fs+0x1f0/0xa00 [btrfs]
  Call trace:
   btrfs_trim_fs+0x34c/0xa00 [btrfs f02c1d570ceea621c69d302ba75dd61868083840] (P)
   btrfs_ioctl_fitrim+0xe8/0x178 [btrfs f02c1d570ceea621c69d302ba75dd61868083840]
   btrfs_ioctl+0xdd4/0x2bd8 [btrfs f02c1d570ceea621c69d302ba75dd61868083840]
   __arm64_sys_ioctl+0xac/0x108
   invoke_syscall.constprop.0+0x5c/0xd0
   el0_svc_common.constprop.0+0x40/0xf0
   do_el0_svc+0x24/0x40
   el0_svc+0x40/0x1d0
   el0t_64_sync_handler+0xa0/0xe8
   el0t_64_sync+0x1b0/0x1b8
  Code: 17ffff83 f94017e0 f9002be0 f9402ea0 (f9400c00)
  ---[ end trace 0000000000000000  ]---

Also the reporter is very kind to test the following ASSERT() added to
btrfs_trim_free_extents_throttle():

	ASSERT(device->bdev,
	       "devid=%llu path=%s dev_state=0x%lx\n",
	       device->devid, btrfs_dev_name(device), device->dev_state);

And it shows the following output:

  assertion failed: device->bdev, in extent-tree.c:6630 (devid=2 path=/dev/sdd dev_state=0x82)

Which means the device->bdev is NULL, and the dev_state is
BTRFS_DEV_STATE_IN_FS_METADATA | BTRFS_DEV_STATE_ITEM_FOUND, without
BTRFS_DEV_STATE_WRITEABLE flag set.

[CAUSE]
The pc points to the following call chain:

  btrfs_trim_fs()
  |- btrfs_trim_free_extents()
     |- btrfs_trim_free_extents_throttle()
        |- bdev_max_discard_sectors(device->bdev)

So the NULL pointer dereference is caused by device->bdev being NULL.

This looks impossible by a quick glance, as just before calling
btrfs_trim_free_extents_throttle(), we have skipped any device that has
BTRFS_DEV_STATE_MISSING flag set.

However in this particular case, there is a window where the missing
device is later re-scanned, causing btrfs to remove the
BTRFS_DEV_STATE_MISSING flag:

  btrfs_control_ioctl()
  |- btrfs_scan_one_device()
     |- device_list_add()
        |- rcu_assign_pointer(device->name, name);
        |  This updates the missing device's path to the new good path.
        |
        |- clear_bit(BTRFS_DEV_STATE_MISSING, &device->dev_state)
           This removes the BTRFS_DEV_STATE_MISSING flag.

This allows the missing device to re-appear and clear the
BTRFS_DEV_STATE_MISSING flag.  However the device still does not have
the BTRFS_DEV_STATE_WRITEABLE flag set, nor is its bdev pointer updated.

The bdev pointer remains NULL, triggering the crash later.

[FIX]
This is a big de-synchronization between BTRFS_DEV_STATE_MISSING and
device->bdev pointer, and shows a gap in btrfs's re-appearing-device
handling.

The proper handling of re-appearing device will need quite some extra
work, which is out of the context of this small fix.

Thankfully the regular bbio submission path has already handled it well
by checking if the device->bdev is NULL before submitting.

So here we just fix the crash by checking if the device is writeable and
has a bdev pointer before calling bdev_max_discard_sectors().

Reported-by: Su Yue <glass.su@suse.com>
Link: https://lore.kernel.org/linux-btrfs/wlwir19t.fsf@damenly.org/
Fixes: 499f377f49 ("btrfs: iterate over unused chunk space in FITRIM")
CC: stable@vger.kernel.org # 5.10+
Reviewed-by: Filipe Manana <fdmanana@suse.com>
Signed-off-by: Qu Wenruo <wqu@suse.com>
Signed-off-by: David Sterba <dsterba@suse.com>
2026-06-09 18:22:46 +02:00
Filipe Manana
dad845f192 btrfs: return real error after lookup failure in btrfs_ioctl_default_subvol()
If we fail to lookup the dir item, we are always returning -ENOENT but
that may not be the reason for the failure, as btrfs_lookup_dir_item() can
return many different errors, such as -EIO or -ENOMEM for example.
Fix this by returning the real error, and also fixup the silly error
message, including the id of the directory and the error.

Reviewed-by: Qu Wenruo <wqu@suse.com>
Signed-off-by: Filipe Manana <fdmanana@suse.com>
Reviewed-by: David Sterba <dsterba@suse.com>
Signed-off-by: David Sterba <dsterba@suse.com>
2026-06-09 18:22:46 +02:00
Filipe Manana
00608e3416 btrfs: use mapping shared locking for reading super block
There's no need to exclusively lock the mapping, shared locking is enough
to protect from a concurrent set block size operation (BLKBSZSET ioctl).

Reviewed-by: Qu Wenruo <wqu@suse.com>
Signed-off-by: Filipe Manana <fdmanana@suse.com>
Signed-off-by: David Sterba <dsterba@suse.com>
2026-06-09 18:22:46 +02:00
Ben Maurer
1ba72d847c btrfs: use lockless read in nr_cached_objects shrinker callback
Under heavy memcg-driven slab reclaim with many memcgs and CPUs,
shrink_slab_memcg() invokes the per-superblock count callback once per
(memcg, NUMA node) tuple. For btrfs that callback reaches
percpu_counter_sum_positive() on fs_info->evictable_extent_maps, which
takes the percpu_counter's raw spinlock with IRQs disabled and walks
every online CPU. With hundreds of memcgs driving reclaim on a host with
dozens of CPUs, this counter lock becomes a global serialization point:
profiles show CPU pinned in the spin_lock_irqsave acquire under
__percpu_counter_sum, with cross-CPU IPIs hitting csd_lock_wait_toolong
while waiting for spinning vCPUs.

The shrinker count is advisory -- super_cache_count() already notes
"counts can change between super_cache_count and super_cache_scan, so we
really don't need locks here." Use percpu_counter_read_positive(), which
is lockless. Worst-case skew is bounded by batch * num_online_cpus (a
few thousand), negligible compared to the millions of extent maps a busy
filesystem accumulates and well within the noise that the shrinker
already tolerates.

Tested-by: Boris Burkov <boris@bur.io>
Reviewed-by: Qu Wenruo <wqu@suse.com>
Reviewed-by: Shakeel Butt <shakeel.butt@linux.dev>
Signed-off-by: Ben Maurer <bmaurer@meta.com>
Signed-off-by: David Sterba <dsterba@suse.com>
2026-06-09 18:22:46 +02:00
David Sterba
79bdd88463 btrfs: switch local indicator variables to bools
For all local indicator variables do simple switch to bool, done on all
files.

Signed-off-by: David Sterba <dsterba@suse.com>
2026-06-09 18:22:46 +02:00
David Sterba
18a8071177 btrfs: send: pass bool for pending_move and refs_processed parameters
We're passing simple indicators as int, switch them to bool types.

Signed-off-by: David Sterba <dsterba@suse.com>
2026-06-09 18:22:45 +02:00
David Sterba
422ccdfe22 btrfs: use shifts for sectorsize and nodesize
Convert more multiplications of sectorsize or nodesize to use the
shifts. The remaining cases are multiplications by constants that
compiler can optimize by itself, and in tests.

Reviewed-by: Qu Wenruo <wqu@suse.com>
Reviewed-by: Boris Burkov <boris@bur.io>
Signed-off-by: David Sterba <dsterba@suse.com>
2026-06-09 18:22:45 +02:00
Filipe Manana
532085d00e btrfs: fix deadlock cloning inline extent when using flushoncommit
In commit b48c980b6a ("btrfs: fix deadlock between reflink and
transaction commit when using flushoncommit") a deadlock was fixed
between reflinks and transaction commits when the fs is mounted with the
flushoncommit option. This happened when we had to copy an inline extent's
data to the destination file. However the issue was fixed only for the
case where the destination offset is 0, it missed the case when the offset
is greater than zero.

Fix this by ensuring we get i_size update whenever we copied an inline
extent's data into the destination file.

Syzbot reported this with the following trace:

   INFO: task kworker/u8:3:57 blocked for more than 143 seconds.
         Not tainted syzkaller #0
   "echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message.
   task:kworker/u8:3    state:D stack:21600 pid:57    tgid:57    ppid:2      task_flags:0x4208160 flags:0x00080000
   Workqueue: writeback wb_workfn (flush-btrfs-129)
   Call Trace:
    <TASK>
    context_switch kernel/sched/core.c:5402 [inline]
    __schedule+0x16f9/0x5500 kernel/sched/core.c:7204
    __schedule_loop kernel/sched/core.c:7283 [inline]
    schedule+0x164/0x360 kernel/sched/core.c:7298
    wait_extent_bit fs/btrfs/extent-io-tree.c:905 [inline]
    btrfs_lock_extent_bits+0x59c/0x700 fs/btrfs/extent-io-tree.c:2008
    btrfs_lock_extent fs/btrfs/extent-io-tree.h:152 [inline]
    btrfs_invalidate_folio+0x440/0xc00 fs/btrfs/inode.c:7718
    extent_writepage fs/btrfs/extent_io.c:1848 [inline]
    extent_write_cache_pages fs/btrfs/extent_io.c:2552 [inline]
    btrfs_writepages+0x12f3/0x2410 fs/btrfs/extent_io.c:2684
    do_writepages+0x32e/0x550 mm/page-writeback.c:2571
    __writeback_single_inode+0x133/0x10e0 fs/fs-writeback.c:1764
    writeback_sb_inodes+0x97f/0x1980 fs/fs-writeback.c:2056
    wb_writeback+0x445/0xb00 fs/fs-writeback.c:2241
    wb_do_writeback fs/fs-writeback.c:2388 [inline]
    wb_workfn+0x3fd/0xf20 fs/fs-writeback.c:2428
    process_one_work+0x98b/0x1630 kernel/workqueue.c:3318
    process_scheduled_works kernel/workqueue.c:3401 [inline]
    worker_thread+0xb49/0x1140 kernel/workqueue.c:3482
    kthread+0x388/0x470 kernel/kthread.c:436
    ret_from_fork+0x514/0xb70 arch/x86/kernel/process.c:158
    ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:245
    </TASK>
   INFO: task syz.0.145:8523 blocked for more than 143 seconds.
         Not tainted syzkaller #0
   "echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message.
   task:syz.0.145       state:D stack:22752 pid:8523  tgid:8522  ppid:5850   task_flags:0x400140 flags:0x00080002
   Call Trace:
    <TASK>
    context_switch kernel/sched/core.c:5402 [inline]
    __schedule+0x16f9/0x5500 kernel/sched/core.c:7204
    __schedule_loop kernel/sched/core.c:7283 [inline]
    schedule+0x164/0x360 kernel/sched/core.c:7298
    wb_wait_for_completion+0x3e8/0x790 fs/fs-writeback.c:227
    __writeback_inodes_sb_nr+0x24c/0x2d0 fs/fs-writeback.c:2847
    try_to_writeback_inodes_sb+0x9a/0xc0 fs/fs-writeback.c:2895
    btrfs_start_delalloc_flush fs/btrfs/transaction.c:2182 [inline]
    btrfs_commit_transaction+0x813/0x2fc0 fs/btrfs/transaction.c:2371
    btrfs_sync_file+0xdf4/0x1230 fs/btrfs/file.c:1822
    generic_write_sync include/linux/fs.h:2663 [inline]
    btrfs_do_write_iter+0x6a9/0x840 fs/btrfs/file.c:1473
    new_sync_write fs/read_write.c:595 [inline]
    vfs_write+0x629/0xba0 fs/read_write.c:688
    ksys_write+0x156/0x270 fs/read_write.c:740
    do_syscall_x64 arch/x86/entry/syscall_64.c:63 [inline]
    do_syscall_64+0x15f/0x560 arch/x86/entry/syscall_64.c:94
    entry_SYSCALL_64_after_hwframe+0x77/0x7f
   RIP: 0033:0x7f5a0bdece59
   RSP: 002b:00007f5a0b446028 EFLAGS: 00000246 ORIG_RAX: 0000000000000001
   RAX: ffffffffffffffda RBX: 00007f5a0c065fa0 RCX: 00007f5a0bdece59
   RDX: 000000000000029f RSI: 0000200000000200 RDI: 0000000000000004
   RBP: 00007f5a0be82d6f R08: 0000000000000000 R09: 0000000000000000
   R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000000
   R13: 00007f5a0c066038 R14: 00007f5a0c065fa0 R15: 00007ffe149206b8
    </TASK>
   INFO: task syz.0.145:8539 blocked for more than 143 seconds.
         Not tainted syzkaller #0
   "echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message.
   task:syz.0.145       state:D stack:23704 pid:8539  tgid:8522  ppid:5850   task_flags:0x400140 flags:0x00080002
   Call Trace:
    <TASK>
    context_switch kernel/sched/core.c:5402 [inline]
    __schedule+0x16f9/0x5500 kernel/sched/core.c:7204
    __schedule_loop kernel/sched/core.c:7283 [inline]
    schedule+0x164/0x360 kernel/sched/core.c:7298
    wait_current_trans+0x39f/0x590 fs/btrfs/transaction.c:536
    start_transaction+0xbd8/0x1820 fs/btrfs/transaction.c:716
    clone_copy_inline_extent fs/btrfs/reflink.c:299 [inline]
    btrfs_clone+0x1316/0x2540 fs/btrfs/reflink.c:574
    btrfs_clone_files+0x271/0x3f0 fs/btrfs/reflink.c:795
    btrfs_remap_file_range+0x76b/0x1320 fs/btrfs/reflink.c:948
    vfs_clone_file_range+0x435/0x7b0 fs/remap_range.c:403
    ioctl_file_clone fs/ioctl.c:239 [inline]
    ioctl_file_clone_range fs/ioctl.c:257 [inline]
    do_vfs_ioctl+0xe15/0x1540 fs/ioctl.c:544
    __do_sys_ioctl fs/ioctl.c:595 [inline]
    __se_sys_ioctl+0x82/0x170 fs/ioctl.c:583
    do_syscall_x64 arch/x86/entry/syscall_64.c:63 [inline]
    do_syscall_64+0x15f/0x560 arch/x86/entry/syscall_64.c:94
    entry_SYSCALL_64_after_hwframe+0x77/0x7f
   RIP: 0033:0x7f5a0bdece59
   RSP: 002b:00007f5a0b425028 EFLAGS: 00000246 ORIG_RAX: 0000000000000010
   RAX: ffffffffffffffda RBX: 00007f5a0c066090 RCX: 00007f5a0bdece59
   RDX: 00002000000000c0 RSI: 000000004020940d RDI: 0000000000000004
   RBP: 00007f5a0be82d6f R08: 0000000000000000 R09: 0000000000000000
   R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000000
   R13: 00007f5a0c066128 R14: 00007f5a0c066090 R15: 00007ffe149206b8
    </TASK>

Reported-by: syzbot+c7443384724bb0f9e913@syzkaller.appspotmail.com
Link: https://lore.kernel.org/linux-btrfs/6a150a09.820a0220.e7972.0006.GAE@google.com/
Fixes: 05a5a7621c ("Btrfs: implement full reflink support for inline extents")
Reviewed-by: Boris Burkov <boris@bur.io>
Signed-off-by: Filipe Manana <fdmanana@suse.com>
Signed-off-by: David Sterba <dsterba@suse.com>
2026-06-09 18:22:45 +02:00
Rik van Riel
23fd95663b btrfs: allocate eb-attached btree pages as movable
Extent buffer pages allocated by alloc_extent_buffer() are attached to
btree_inode->i_mapping (the buffer_tree path), reach the LRU, and are
served by the btree_migrate_folio aops in fs/btrfs/disk-io.c. They are
migratable in practice once their owning extent buffer hits refs == 1,
which happens naturally. The buddy allocator classifies them by GFP,
however, and bare GFP_NOFS lands them in MIGRATE_UNMOVABLE pageblocks.

The result: every btree_inode page we read in pins an unmovable pageblock
from the page-superblock allocator's perspective, even though the page
itself can be moved.

Have each caller of btrfs_alloc_page_array, btrfs_alloc_folio_array,
and alloc_eb_folio_array pass in the full GFP mask directly, instead
of having the functions calculate it from boolean flags.

The alloc_extent_buffer call site passes GFP_NOFS | __GFP_NOFAIL |
__GFP_MOVABLE. All other call sites pass plain GFP_NOFS.

Three categories of caller stay on bare GFP_NOFS, deliberately:

  - alloc_dummy_extent_buffer / btrfs_clone_extent_buffer: the
    resulting eb is EXTENT_BUFFER_UNMAPPED, folio->mapping stays NULL,
    the folios never enter LRU, never get migrate_folio aops. Tagging
    them __GFP_MOVABLE would violate the page allocator's migrability
    contract and they would defeat compaction in MOVABLE pageblocks
    where isolate_migratepages_block skips non-LRU non-movable_ops
    pages outright.

  - btrfs_alloc_page_array callers in fs/btrfs/raid56.c (stripe
    pages), fs/btrfs/inode.c (encoded reads), fs/btrfs/ioctl.c (io_uring
    encoded reads), fs/btrfs/relocation.c (relocation buffers): same
    contract violation. raid56 stripe_pages additionally persist in
    the stripe cache (RBIO_CACHE_SIZE=1024) well beyond a single I/O,
    so they are not transient enough to hand-wave the contract.

  - btrfs_alloc_folio_array caller in fs/btrfs/scrub.c (stripe
    folios): same -- stripe->folios[] are private buffers freed via
    folio_put in release_scrub_stripe.

This change targets the dominant fragmentation source observed on the
page-superblock series: ~28 GB of btree_inode pages parked across
many tainted superpageblocks on a 250 GB test system with btrfs root,
preventing 1 GiB hugepage allocation from those regions. With the
movable hint, those pages now land in MOVABLE pageblocks where the
existing background defragger drains them through the standard
PB_has_movable gate, no LRU-sample fallback needed.

Assisted-by: Claude:claude-opus-4-6
Signed-off-by: Rik van Riel <riel@surriel.com>
Signed-off-by: David Sterba <dsterba@suse.com>
2026-06-09 18:22:45 +02:00
Daan De Meyer
538e5bdbc8 btrfs: add 32-bit compat ioctl for BTRFS_IOC_GET_SUBVOL_INFO
On 64-bit kernels with 32-bit userspace, struct btrfs_ioctl_timespec is
laid out as 16 bytes (8B sec + 4B nsec + 4B trailing padding) instead of
the 12 bytes a 32-bit userspace expects, because the surrounding struct
is not packed. As a result, struct btrfs_ioctl_get_subvol_info_args has
a different size and layout in 32-bit userspace than in the 64-bit
kernel, and BTRFS_IOC_GET_SUBVOL_INFO returns garbage to 32-bit callers.

Mirror what was done for BTRFS_IOC_SET_RECEIVED_SUBVOL: add a packed
btrfs_ioctl_get_subvol_info_args_32 with btrfs_ioctl_timespec_32 fields,
define BTRFS_IOC_GET_SUBVOL_INFO_32 with that struct as the size
argument, factor the existing handler into a shared _btrfs_ioctl_get_
subvol_info() helper, and add btrfs_ioctl_get_subvol_info_32() which
fills the kernel struct and translates field-by-field into the 32-bit
struct before copy_to_user().

Signed-off-by: Daan De Meyer <daan@amutable.com>
Reviewed-by: David Sterba <dsterba@suse.com>
Signed-off-by: David Sterba <dsterba@suse.com>
2026-06-09 18:22:45 +02:00
Anand Jain
c2a74ed049 btrfs: derive f_fsid from on-disk fsid and dev_t
The f_fsid was originally derived from fs_devices->fsid and the
subvolume root ID. However, when temp_fsid is active, fs_devices->fsid
is randomized, making the standard derivation inconsistent.

Since metadata_uuid is optional, it is not a reliable alternative.  This
patch instead retrieves the on-disk UUID from fs_info->super_copy->fsid.

To prevent f_fsid collisions between original and cloned filesystems,
this implementation hashes the dev_t for single-device btrfs filesystems
to ensure uniqueness. This is limited to single-device filesystems as
cloned mounts are currently only supported for that configuration. Note
that f_fsid will change if the device is replaced.

Additionally, since the kernel cannot distinguish between the original
and the cloned filesystem, this new f_fsid derivation is applied to
both.

Link: https://lore.kernel.org/linux-btrfs/cover.1772095546.git.asj@kernel.org/
Link: https://lore.kernel.org/linux-btrfs/cover.1774092915.git.asj@kernel.org/
Signed-off-by: Anand Jain <asj@kernel.org>
Signed-off-by: David Sterba <dsterba@suse.com>
2026-06-09 18:22:45 +02:00
Anand Jain
df84f6c773 btrfs: use on-disk uuid for s_uuid in temp_fsid mounts
When mounting a cloned filesystem with a temporary fsuuid (temp_fsid),
layered modules like overlayfs require a persistent identifier.

While internal in-memory fs_devices->fsid must remain unique to
the kernel module, let s_uuid carry the original on-disk UUID.

Signed-off-by: Anand Jain <asj@kernel.org>
Signed-off-by: David Sterba <dsterba@suse.com>
2026-06-09 18:22:45 +02:00
Qu Wenruo
5d40d064db btrfs: avoid unnecessary dev stats updates
[MINOR PROBLEM]
When mounting a filesystem with a valid DEV_STATS item, we will always
update the DEV_STATS again in the next transaction commit, even if there
is no change the values.

[CAUSE]
During the mount, btrfs_device_init_dev_stats() will read out the
on-disk DEV_STATS item for each device.
Then it calls btrfs_dev_stat_set() to update the in-memory structure.

However btrfs_dev_stat_set() does not only set the dev stats value, but
also increase device->dev_stats_ccnt.

That member determines if we should update the device item at the next
transaction commit. Since we have called btrfs_dev_stat_set() for each
dev status member, dev_stats_ccnt will be non-zero and we will update
the dev stats item even it doesn't change at all.

[FIX]
Instead of using btrfs_dev_stat_set() for valid on-disk DEV_STATUS
values, directly call atomic_set() to set the in-memory values.

For other call sites, we still want to use btrfs_dev_stat_set() so that
we will force updating/creating the dev stats item.

Signed-off-by: Qu Wenruo <wqu@suse.com>
Signed-off-by: David Sterba <dsterba@suse.com>
2026-06-09 18:22:45 +02:00
Qu Wenruo
923546d3c3 btrfs: always update/create the dev stats item when adding a new device
[MINOR PROBLEM]
When adding a new btrfs device, the corresponding DEV_STATS item creation
can only triggered by a mount cycle if there is no other error
triggered:

  # mkfs.btrfs -f $dev1 $mnt
  # mount $dev1 $mnt
  # btrfs dev add $dev2 $mnt
  # sync
  # btrfs ins dump-tree -t dev $dev1
  device tree key (DEV_TREE ROOT_ITEM 0)
  leaf 30588928 items 6 free space 15853 generation 9 owner DEV_TREE
         item 0 key (DEV_STATS PERSISTENT_ITEM 1) itemoff 16243 itemsize 40 <<<
         	persistent item objectid DEV_STATS offset 1
         	device stats
         	write_errs 0 read_errs 0 flush_errs 0 corruption_errs 0 generation 0
         item 1 key (1 DEV_EXTENT 13631488) itemoff 16195 itemsize 48

Only after a mount cycle and a new transaction, the DEV_STATS for devid
2 can show up:

  # umount $mnt
  # mount $dev1 $mnt
  # touch $mnt
  # sync
  # btrfs ins dump-tree -t dev $dev1
  device tree key (DEV_TREE ROOT_ITEM 0)
  leaf 30605312 items 7 free space 15788 generation 10 owner DEV_TREE
         item 0 key (DEV_STATS PERSISTENT_ITEM 1) itemoff 16243 itemsize 40
         	persistent item objectid DEV_STATS offset 1
         	device stats
         	write_errs 0 read_errs 0 flush_errs 0 corruption_errs 0 generation 0
         item 1 key (DEV_STATS PERSISTENT_ITEM 2) itemoff 16203 itemsize 40
         	persistent item objectid DEV_STATS offset 2
         	device stats
         	write_errs 0 read_errs 0 flush_errs 0 corruption_errs 0 generation 0

[CAUSE]
Btrfs only updates the DEV_STATS item when the device->dev_stats_ccnt
counter is not 0.

This is to reduce COW for the device tree. However that dev_stats_ccnt is
only increased at the following call sites:

- btrfs_dev_stat_inc()
  This happens when some IO error happened.

- btrfs_dev_stat_read_and_reset()
  This happens for GET_DEV_STATS ioctl with BTRFS_DEV_STATS_RESET flag.

- btrfs_dev_stat_set()
  This happens inside btrfs_device_init_dev_stats().

So when a new device is added, its dev_stats_ccnt is just initialized to
0, and btrfs won't create nor update the corresponding DEV_STATS item at
all.

[ENHANCEMENT]
When a new device is added, also increase the dev_stats_ccnt by one.
This includes both device add ioctl and dev-replace.

This will force btrfs to create a new DEV_STATS item or update the
existing one with the correct values.

This not only makes the DEV_STATS creation early, but also prevents
old DEV_STATS left from older kernels to cause false alerts for the
newly added device.

Signed-off-by: Qu Wenruo <wqu@suse.com>
Signed-off-by: David Sterba <dsterba@suse.com>
2026-06-09 18:22:45 +02:00
Qu Wenruo
052273b63d btrfs: remove the dev stats item when removing a device
[MINOR BUG]
The following script will cause DEV_STATS item to be left after the
corresponding device is removed:

  # mkfs.btrfs -f $dev1
  # mount $dev1 $mnt
  # btrfs dev add $dev2 $mnt
  # umount $mnt

  ## Without real errors, only at mount time btrfs will update
  ## dev->dev_stats_ccnt, thus we need a mount cycle to create the
  ## DEV_STATS item for the new device.

  # mount $dev1 $mnt
  # touch $mnt/foobar
  # sync
  # btrfs dev remove $dev2 $mnt
  # umount $mnt

This will result the DEV_STATS item for devid 2 still left in device
tree:

  device tree key (DEV_TREE ROOT_ITEM 0)
  leaf 31064064 items 7 free space 15788 generation 18 owner DEV_TREE
  leaf 31064064 flags 0x1(WRITTEN) backref revision 1
  fs uuid 4bd853ed-f6ef-45fd-bbf1-1c3a2d9987cb
  chunk uuid b496eab1-ec23-46b5-81c1-2f1b3503ca07
         item 0 key (DEV_STATS PERSISTENT_ITEM 1) itemoff 16243 itemsize 40
         	persistent item objectid DEV_STATS offset 1
         	device stats
         	write_errs 0 read_errs 0 flush_errs 0 corruption_errs 0 generation 0
         item 1 key (DEV_STATS PERSISTENT_ITEM 2) itemoff 16203 itemsize 40
         	persistent item objectid DEV_STATS offset 2
         	device stats
         	write_errs 0 read_errs 0 flush_errs 0 corruption_errs 0 generation 0

This is not a huge problem, but if the existing DEV_STATS contains
errors, and a new device is added into the fs taking the old devid, then
after a mount cycle, the new device will suddenly inherit old errors
which can give false alerts.

[CAUSE]
Btrfs never has the ability to delete DEV_STATS items.

It either create a new one through update_dev_stat_item(), or read an
existing one through btrfs_device_init_dev_stats().

However update_dev_stat_item() is only called lazily, if a new device is
created and no new update to dev stats, then it will skip the update of
the on-disk item.

So if the old DEV_STATS item exists and a new device is added, and no
errors during the remaining operations, the old DEV_STATS will not be
updated.

Then at the next mount cycle, btrfs_device_init_dev_stats() is called at
mount time, which will read out the old records, causing false alerts to
the newly added device.

[FIX]
Manually remove the DEV_STATS item during btrfs_rm_device().

Signed-off-by: Qu Wenruo <wqu@suse.com>
Signed-off-by: David Sterba <dsterba@suse.com>
2026-06-09 18:22:45 +02:00
Qu Wenruo
15a12af71c btrfs: remove the dev stats item for replace target device
[MINOR PROBLEM]
When a running dev-replace hits some error for the target device (devid
0), there will be a DEV_STATS with error records created at the next
transaction commit.

Unfortunately that item will never to be deleted.

This means at the next dev-replace, if the replace is interrupted, then
at the next mount, the target device will suddenly inherit the old error
records from that DEV_STATS item, which can give some false alerts on
that device.

This shouldn't affect end users that much, as it requires all the
following conditions to be met, which is pretty rare:

- The initial dev-replace hits some error on the target device
  E.g. write errors, but those errors itself is already a big problem
  for a running replace.

  This is required to create the DEV_STATS item in the first place.

- The next replace is interrupted
  This is required to allow btrfs to read from the old records.

[CAUSE]
Btrfs just never deletes the DEV_STATS after a replace is finished.

[FIX]
Remove the DEV_STATS item for devid 0 after the replace is finished.

This is not going to completely fix the error, as we still have other
error paths, e.g. by somehow the fs flips RO and can not start a new
transaction for the DEV_STATS item removal.

But those corner cases will be addressed by later patches which provide
a more generic fix to DEV_STATS related problems.

Signed-off-by: Qu Wenruo <wqu@suse.com>
Signed-off-by: David Sterba <dsterba@suse.com>
2026-06-09 18:22:44 +02:00
Teng Liu
a6908f88c9 btrfs: validate data reloc tree file extent item members
get_new_location() uses BUG_ON() to crash the kernel if the file extent
item it looks up has any of offset, compression, encryption, or
other_encoding set non-zero. The data reloc inode is only written by
relocation's own paths and the four fields are always 0 in what the
kernel writes:

  - insert_prealloc_file_extent() memsets the stack item to zero and
    only fills in type, disk_bytenr, disk_num_bytes and num_bytes, so
    offset/compression/encryption/other_encoding stay 0.
  - insert_ordered_extent_file_extent() copies oe->compress_type into
    the file extent's compression field, but the data reloc inode is
    created with BTRFS_INODE_NOCOMPRESS so compress_type is always 0;
    encryption and other_encoding are reserved-and-zero in btrfs.

A non-zero value here means the leaf decoded from disk does not match
what the kernel wrote, i.e. on-disk corruption. A malformed image
reaches this code via balance and panics the kernel.

A previous attempt to enforce all four constraints in tree-checker's
check_extent_data_item() was merged as commit 7d0ee95979e9 ("btrfs:
validate data reloc tree file extent item members in tree-checker")
and then reverted by commit 1c034697fcaa after btrfs/061 produced
false positives on arm64 with 64K pages. The reason: relocation
writeback legitimately produces REG file_extent_items with offset != 0
in the data reloc tree. When an ordered extent covers only the back
portion of an underlying PREALLOC (num_bytes < ram_bytes on the input
file_extent), insert_ordered_extent_file_extent() inserts a REG with

  offset    = oe->offset
  num_bytes = oe->num_bytes
  ram_bytes preserved from the original PREALLOC,

and this item can reach disk if a transaction commit fires while it
is present in the leaf.

The four fields belong in different layers:

  - compression, encryption and other_encoding are universal
    invariants for every item in the data reloc tree, regardless of
    cluster geometry. Enforce them in tree-checker's
    check_extent_data_item() so a corrupt leaf is rejected at read
    time.

  - offset is only an invariant at the cluster-boundary keys that
    get_new_location() searches (the key is computed as
    src_disk_bytenr - reloc_block_group_start). Partial-PREALLOC
    writebacks legitimately place REG items at non-boundary keys with
    offset != 0; tree-checker cannot reject these. The cluster-
    boundary item is always written by either
    insert_prealloc_file_extent() (offset=0 by memset) or by the
    front portion of a partial writeback (offset=0 by construction),
    so a non-zero offset there is corruption.

Enforce the universal invariants in check_extent_data_item() with a
file_extent_err() rejection. Convert the BUG_ON() in
get_new_location() to a -EUCLEAN return paired with btrfs_print_leaf()
and btrfs_err() so the offending leaf is logged. The caller in
replace_file_extents() already handles non-zero returns from
get_new_location() by breaking out of the loop without aborting the
transaction.

Suggested-by: Qu Wenruo <wqu@suse.com>
Suggested-by: David Sterba <dsterba@suse.com>
Reported-by: syzbot+3e20d8f3d41bac5dc9a2@syzkaller.appspotmail.com
Closes: https://syzkaller.appspot.com/bug?extid=3e20d8f3d41bac5dc9a2
Signed-off-by: Teng Liu <27rabbitlt@gmail.com>
Signed-off-by: David Sterba <dsterba@suse.com>
2026-06-09 18:22:44 +02:00