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1,267,977 commits

Author SHA1 Message Date
Dmitry Baryshkov
eeb403df95 ARM: dts: imx53-qsb: add support for the HDMI expander
Add support for the MCIMXHDMICARD expansion card attached to the iMX53
QSB / QSRB platforms. This enables HDMI output on those devices.

Reviewed-by: Fabio Estevam <festevam@gmail.com>
Signed-off-by: Dmitry Baryshkov <dmitry.baryshkov@linaro.org>
Tested-by: Fabio Estevam <festevam@gmail.com>
Signed-off-by: Shawn Guo <shawnguo@kernel.org>
2024-02-23 12:01:57 +08:00
Marek Vasut
340d538e3b arm64: dts: imx8mp: Enable SAI audio on Data Modul i.MX8M Plus eDM SBC
Add SAI I2S and audio bindings to Data Modul i.MX8M Plus eDM SBC.

The SGTL5000 is attached to SAI3, however the SGTL5000 codec MCLK
must be supplied even if the SAI3 is not in use and is controlled
separately by the codec. The MCLK is also used to drive the codec
I2C block, so without MCLK, I2C access to the codec would not be
possible.

To provide such flexible MCLK control, use PWM4 with period 1 and
duty cycle 50% as 12 MHz clock source, as there is no direct way
to route MX8MP CCM clock to the MCLK pin. Use codec as bitclock
and frame clock master, so that the SGTL5000 PLL can be used to
generate derived clock.

Signed-off-by: Marek Vasut <marex@denx.de>
Signed-off-by: Shawn Guo <shawnguo@kernel.org>
2024-02-23 12:00:46 +08:00
Alexander Stein
616effc027 arm64: dts: imx8: Fix lpuart DMA channel order
Bindings say DMA channels are in order Rx, Tx. Adjust the DT nodes
accordingly. While at it, use defines for the flags.

Signed-off-by: Alexander Stein <alexander.stein@ew.tq-group.com>
Signed-off-by: Shawn Guo <shawnguo@kernel.org>
2024-02-23 11:59:31 +08:00
Alexander Stein
30567925e9 arm64: dts: freescale: imx8-ss-dma: Fix edma3's location
Sort nodes by base address. edma3 comes later in the memory map.

Signed-off-by: Alexander Stein <alexander.stein@ew.tq-group.com>
Signed-off-by: Shawn Guo <shawnguo@kernel.org>
2024-02-23 11:58:19 +08:00
Jeremy Kerr
3773d65ae5 net: mctp: take ownership of skb in mctp_local_output
Currently, mctp_local_output only takes ownership of skb on success, and
we may leak an skb if mctp_local_output fails in specific states; the
skb ownership isn't transferred until the actual output routing occurs.

Instead, make mctp_local_output free the skb on all error paths up to
the route action, so it always consumes the passed skb.

Fixes: 833ef3b91d ("mctp: Populate socket implementation")
Signed-off-by: Jeremy Kerr <jk@codeconstruct.com.au>
Reviewed-by: Simon Horman <horms@kernel.org>
Link: https://lore.kernel.org/r/20240220081053.1439104-1-jk@codeconstruct.com.au
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
2024-02-22 19:21:11 -08:00
Jakub Kicinski
e872469c38 Merge branch '100GbE' of git://git.kernel.org/pub/scm/linux/kernel/git/tnguy/net-queue
Tony Nguyen says:

====================
Intel Wired LAN Driver Updates 2024-02-20 (ice)

This series contains updates to ice driver only.

Yochai sets parent device to properly reflect connection state between
source DPLL and output pin.

Arkadiusz fixes additional issues related to DPLL; proper reporting of
phase_adjust value and preventing use/access of data while resetting.

Amritha resolves ASSERT_RTNL() being triggered on certain reset/rebuild
flows.

* '100GbE' of git://git.kernel.org/pub/scm/linux/kernel/git/tnguy/net-queue:
  ice: Fix ASSERT_RTNL() warning during certain scenarios
  ice: fix pin phase adjust updates on PF reset
  ice: fix dpll periodic work data updates on PF reset
  ice: fix dpll and dpll_pin data access on PF reset
  ice: fix dpll input pin phase_adjust value updates
  ice: fix connection state of DPLL and out pin
====================

Reviewed-by: Vadim Fedorenko <vadim.fedorenko@linux.dev>
Reviewed-by: Jiri Pirko <jiri@nvidia.com>
Link: https://lore.kernel.org/r/20240220214444.1039759-1-anthony.l.nguyen@intel.com
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
2024-02-22 19:19:37 -08:00
Florian Westphal
5ae1e9922b net: ip_tunnel: prevent perpetual headroom growth
syzkaller triggered following kasan splat:
BUG: KASAN: use-after-free in __skb_flow_dissect+0x19d1/0x7a50 net/core/flow_dissector.c:1170
Read of size 1 at addr ffff88812fb4000e by task syz-executor183/5191
[..]
 kasan_report+0xda/0x110 mm/kasan/report.c:588
 __skb_flow_dissect+0x19d1/0x7a50 net/core/flow_dissector.c:1170
 skb_flow_dissect_flow_keys include/linux/skbuff.h:1514 [inline]
 ___skb_get_hash net/core/flow_dissector.c:1791 [inline]
 __skb_get_hash+0xc7/0x540 net/core/flow_dissector.c:1856
 skb_get_hash include/linux/skbuff.h:1556 [inline]
 ip_tunnel_xmit+0x1855/0x33c0 net/ipv4/ip_tunnel.c:748
 ipip_tunnel_xmit+0x3cc/0x4e0 net/ipv4/ipip.c:308
 __netdev_start_xmit include/linux/netdevice.h:4940 [inline]
 netdev_start_xmit include/linux/netdevice.h:4954 [inline]
 xmit_one net/core/dev.c:3548 [inline]
 dev_hard_start_xmit+0x13d/0x6d0 net/core/dev.c:3564
 __dev_queue_xmit+0x7c1/0x3d60 net/core/dev.c:4349
 dev_queue_xmit include/linux/netdevice.h:3134 [inline]
 neigh_connected_output+0x42c/0x5d0 net/core/neighbour.c:1592
 ...
 ip_finish_output2+0x833/0x2550 net/ipv4/ip_output.c:235
 ip_finish_output+0x31/0x310 net/ipv4/ip_output.c:323
 ..
 iptunnel_xmit+0x5b4/0x9b0 net/ipv4/ip_tunnel_core.c:82
 ip_tunnel_xmit+0x1dbc/0x33c0 net/ipv4/ip_tunnel.c:831
 ipgre_xmit+0x4a1/0x980 net/ipv4/ip_gre.c:665
 __netdev_start_xmit include/linux/netdevice.h:4940 [inline]
 netdev_start_xmit include/linux/netdevice.h:4954 [inline]
 xmit_one net/core/dev.c:3548 [inline]
 dev_hard_start_xmit+0x13d/0x6d0 net/core/dev.c:3564
 ...

The splat occurs because skb->data points past skb->head allocated area.
This is because neigh layer does:
  __skb_pull(skb, skb_network_offset(skb));

... but skb_network_offset() returns a negative offset and __skb_pull()
arg is unsigned.  IOW, we skb->data gets "adjusted" by a huge value.

The negative value is returned because skb->head and skb->data distance is
more than 64k and skb->network_header (u16) has wrapped around.

The bug is in the ip_tunnel infrastructure, which can cause
dev->needed_headroom to increment ad infinitum.

The syzkaller reproducer consists of packets getting routed via a gre
tunnel, and route of gre encapsulated packets pointing at another (ipip)
tunnel.  The ipip encapsulation finds gre0 as next output device.

This results in the following pattern:

1). First packet is to be sent out via gre0.
Route lookup found an output device, ipip0.

2).
ip_tunnel_xmit for gre0 bumps gre0->needed_headroom based on the future
output device, rt.dev->needed_headroom (ipip0).

3).
ip output / start_xmit moves skb on to ipip0. which runs the same
code path again (xmit recursion).

4).
Routing step for the post-gre0-encap packet finds gre0 as output device
to use for ipip0 encapsulated packet.

tunl0->needed_headroom is then incremented based on the (already bumped)
gre0 device headroom.

This repeats for every future packet:

gre0->needed_headroom gets inflated because previous packets' ipip0 step
incremented rt->dev (gre0) headroom, and ipip0 incremented because gre0
needed_headroom was increased.

For each subsequent packet, gre/ipip0->needed_headroom grows until
post-expand-head reallocations result in a skb->head/data distance of
more than 64k.

Once that happens, skb->network_header (u16) wraps around when
pskb_expand_head tries to make sure that skb_network_offset() is unchanged
after the headroom expansion/reallocation.

After this skb_network_offset(skb) returns a different (and negative)
result post headroom expansion.

The next trip to neigh layer (or anything else that would __skb_pull the
network header) makes skb->data point to a memory location outside
skb->head area.

v2: Cap the needed_headroom update to an arbitarily chosen upperlimit to
prevent perpetual increase instead of dropping the headroom increment
completely.

Reported-and-tested-by: syzbot+bfde3bef047a81b8fde6@syzkaller.appspotmail.com
Closes: https://groups.google.com/g/syzkaller-bugs/c/fL9G6GtWskY/m/VKk_PR5FBAAJ
Fixes: 243aad830e ("ip_gre: include route header_len in max_headroom calculation")
Signed-off-by: Florian Westphal <fw@strlen.de>
Reviewed-by: Simon Horman <horms@kernel.org>
Link: https://lore.kernel.org/r/20240220135606.4939-1-fw@strlen.de
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
2024-02-22 19:18:10 -08:00
Andre Werner
45532b21dc net: smsc95xx: add support for SYS TEC USB-SPEmodule1
This patch adds support for the SYS TEC USB-SPEmodule1 10Base-T1L
ethernet device to the existing smsc95xx driver by adding the new
USB VID/PID pair.

Signed-off-by: Andre Werner <andre.werner@systec-electronic.com>
Link: https://lore.kernel.org/r/20240219053413.4732-1-andre.werner@systec-electronic.com
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
2024-02-22 19:14:06 -08:00
Praveen Kumar Kannoju
a4634aa71f bonding: rate-limit bonding driver inspect messages
Through the routine bond_mii_monitor(), bonding driver inspects and commits
the slave state changes. During the times when slave state change and
failure in aqcuiring rtnl lock happen at the same time, the routine
bond_mii_monitor() reschedules itself to come around after 1 msec to commit
the new state.

During this, it executes the routine bond_miimon_inspect() to re-inspect
the state chane and prints the corresponding slave state on to the console.
Hence we do see a message at every 1 msec till the rtnl lock is acquired
and state chage is committed.

This patch doesn't change how bond functions. It only simply limits this
kind of log flood.

Signed-off-by: Praveen Kumar Kannoju <praveen.kannoju@oracle.com>
Reviewed-by: Simon Horman <horms@kernel.org>
Reviewed-by: Hangbin Liu <liuhangbin@gmail.com>
Acked-by: Jay Vosburgh <jay.vosburgh@canonical.com>
Link: https://lore.kernel.org/r/20240221082752.4660-1-praveen.kannoju@oracle.com
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
2024-02-22 19:13:18 -08:00
Jakub Kicinski
4679f4f123 netfilter pr 2024-21-02
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Merge tag 'nf-next-24-02-21' of https://git.kernel.org/pub/scm/linux/kernel/git/netfilter/nf-next

Florian Westphal says:

====================
netfilter updates for net-next

1. Prefer KMEM_CACHE() macro to create kmem caches, from Kunwu Chan.

Patches 2 and 3 consolidate nf_log NULL checks and introduces
extra boundary checks on family and type to make it clear that no out
of bounds access will happen.  No in-tree user currently passes such
values, but thats not clear from looking at the function.
From Pablo Neira Ayuso.

Patch 4, also from Pablo, gets rid of unneeded conditional in
nft_osf init function.

Patch 5, from myself, fixes erroneous Kconfig dependencies that
came in an earlier net-next pull request. This should get rid
of the xtables related build failure reports.

Patches 6 to 10 are an update to nftables' concatenated-ranges
set type to speed up element insertions.  This series also
compacts a few data structures and cleans up a few oddities such
as reliance on ZERO_SIZE_PTR when asking to allocate a set with
no elements. From myself.

Patches 11 moves the nf_reinject function from the netfilter core
(vmlinux) into the nfnetlink_queue backend, the only location where
this is called from. Also from myself.

Patch 12, from Kees Cook, switches xtables' compat layer to use
unsafe_memcpy because xt_entry_target cannot easily get converted
to a real flexible array (its UAPI and used inside other structs).

* tag 'nf-next-24-02-21' of https://git.kernel.org/pub/scm/linux/kernel/git/netfilter/nf-next:
  netfilter: x_tables: Use unsafe_memcpy() for 0-sized destination
  netfilter: move nf_reinject into nfnetlink_queue modules
  netfilter: nft_set_pipapo: use GFP_KERNEL for insertions
  netfilter: nft_set_pipapo: speed up bulk element insertions
  netfilter: nft_set_pipapo: shrink data structures
  netfilter: nft_set_pipapo: do not rely on ZERO_SIZE_PTR
  netfilter: nft_set_pipapo: constify lookup fn args where possible
  netfilter: xtables: fix up kconfig dependencies
  netfilter: nft_osf: simplify init path
  netfilter: nf_log: validate nf_logger_find_get()
  netfilter: nf_log: consolidate check for NULL logger in lookup function
  netfilter: expect: Simplify the allocation of slab caches in nf_conntrack_expect_init
====================

Link: https://lore.kernel.org/r/20240221112637.5396-1-fw@strlen.de
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
2024-02-22 19:06:20 -08:00
Florian Westphal
9a0d18853c netlink: add nla be16/32 types to minlen array
BUG: KMSAN: uninit-value in nla_validate_range_unsigned lib/nlattr.c:222 [inline]
BUG: KMSAN: uninit-value in nla_validate_int_range lib/nlattr.c:336 [inline]
BUG: KMSAN: uninit-value in validate_nla lib/nlattr.c:575 [inline]
BUG: KMSAN: uninit-value in __nla_validate_parse+0x2e20/0x45c0 lib/nlattr.c:631
 nla_validate_range_unsigned lib/nlattr.c:222 [inline]
 nla_validate_int_range lib/nlattr.c:336 [inline]
 validate_nla lib/nlattr.c:575 [inline]
...

The message in question matches this policy:

 [NFTA_TARGET_REV]       = NLA_POLICY_MAX(NLA_BE32, 255),

but because NLA_BE32 size in minlen array is 0, the validation
code will read past the malformed (too small) attribute.

Note: Other attributes, e.g. BITFIELD32, SINT, UINT.. are also missing:
those likely should be added too.

Reported-by: syzbot+3f497b07aa3baf2fb4d0@syzkaller.appspotmail.com
Reported-by: xingwei lee <xrivendell7@gmail.com>
Closes: https://lore.kernel.org/all/CABOYnLzFYHSnvTyS6zGa-udNX55+izqkOt2sB9WDqUcEGW6n8w@mail.gmail.com/raw
Fixes: ecaf75ffd5 ("netlink: introduce bigendian integer types")
Signed-off-by: Florian Westphal <fw@strlen.de>
Link: https://lore.kernel.org/r/20240221172740.5092-1-fw@strlen.de
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
2024-02-22 19:01:55 -08:00
Breno Leitao
3e7a0dccf0 ipv6/sit: Do not allocate stats in the driver
With commit 34d21de99c ("net: Move {l,t,d}stats allocation to core and
convert veth & vrf"), stats allocation could be done on net core
instead of this driver.

With this new approach, the driver doesn't have to bother with error
handling (allocation failure checking, making sure free happens in the
right spot, etc). This is core responsibility now.

Remove the allocation in the ipv6/sit driver and leverage the network
core allocation.

Signed-off-by: Breno Leitao <leitao@debian.org>
Reviewed-by: Simon Horman <horms@kernel.org>
Reviewed-by: David Ahern <dsahern@kernel.org>
Link: https://lore.kernel.org/r/20240221161732.3026127-1-leitao@debian.org
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
2024-02-22 18:57:53 -08:00
Geert Uytterhoeven
bcc115760f octeon_ep_vf: Improve help text grammar
Add missing articles.
Fix plural vs. singular.
Fix present vs. future.

Reviewed-by: Simon Horman <horms@kernel.org>
Reviewed-by: Sathesh B Edara <sedara@marvell.com>
Signed-off-by: Geert Uytterhoeven <geert+renesas@glider.be>
Link: https://lore.kernel.org/r/b3b97462c3d9eba2ec03dd6d597e63bf49a7365a.1708512706.git.geert+renesas@glider.be
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
2024-02-22 18:56:53 -08:00
Ryosuke Yasuoka
661779e1fc netlink: Fix kernel-infoleak-after-free in __skb_datagram_iter
syzbot reported the following uninit-value access issue [1]:

netlink_to_full_skb() creates a new `skb` and puts the `skb->data`
passed as a 1st arg of netlink_to_full_skb() onto new `skb`. The data
size is specified as `len` and passed to skb_put_data(). This `len`
is based on `skb->end` that is not data offset but buffer offset. The
`skb->end` contains data and tailroom. Since the tailroom is not
initialized when the new `skb` created, KMSAN detects uninitialized
memory area when copying the data.

This patch resolved this issue by correct the len from `skb->end` to
`skb->len`, which is the actual data offset.

BUG: KMSAN: kernel-infoleak-after-free in instrument_copy_to_user include/linux/instrumented.h:114 [inline]
BUG: KMSAN: kernel-infoleak-after-free in copy_to_user_iter lib/iov_iter.c:24 [inline]
BUG: KMSAN: kernel-infoleak-after-free in iterate_ubuf include/linux/iov_iter.h:29 [inline]
BUG: KMSAN: kernel-infoleak-after-free in iterate_and_advance2 include/linux/iov_iter.h:245 [inline]
BUG: KMSAN: kernel-infoleak-after-free in iterate_and_advance include/linux/iov_iter.h:271 [inline]
BUG: KMSAN: kernel-infoleak-after-free in _copy_to_iter+0x364/0x2520 lib/iov_iter.c:186
 instrument_copy_to_user include/linux/instrumented.h:114 [inline]
 copy_to_user_iter lib/iov_iter.c:24 [inline]
 iterate_ubuf include/linux/iov_iter.h:29 [inline]
 iterate_and_advance2 include/linux/iov_iter.h:245 [inline]
 iterate_and_advance include/linux/iov_iter.h:271 [inline]
 _copy_to_iter+0x364/0x2520 lib/iov_iter.c:186
 copy_to_iter include/linux/uio.h:197 [inline]
 simple_copy_to_iter+0x68/0xa0 net/core/datagram.c:532
 __skb_datagram_iter+0x123/0xdc0 net/core/datagram.c:420
 skb_copy_datagram_iter+0x5c/0x200 net/core/datagram.c:546
 skb_copy_datagram_msg include/linux/skbuff.h:3960 [inline]
 packet_recvmsg+0xd9c/0x2000 net/packet/af_packet.c:3482
 sock_recvmsg_nosec net/socket.c:1044 [inline]
 sock_recvmsg net/socket.c:1066 [inline]
 sock_read_iter+0x467/0x580 net/socket.c:1136
 call_read_iter include/linux/fs.h:2014 [inline]
 new_sync_read fs/read_write.c:389 [inline]
 vfs_read+0x8f6/0xe00 fs/read_write.c:470
 ksys_read+0x20f/0x4c0 fs/read_write.c:613
 __do_sys_read fs/read_write.c:623 [inline]
 __se_sys_read fs/read_write.c:621 [inline]
 __x64_sys_read+0x93/0xd0 fs/read_write.c:621
 do_syscall_x64 arch/x86/entry/common.c:52 [inline]
 do_syscall_64+0x44/0x110 arch/x86/entry/common.c:83
 entry_SYSCALL_64_after_hwframe+0x63/0x6b

Uninit was stored to memory at:
 skb_put_data include/linux/skbuff.h:2622 [inline]
 netlink_to_full_skb net/netlink/af_netlink.c:181 [inline]
 __netlink_deliver_tap_skb net/netlink/af_netlink.c:298 [inline]
 __netlink_deliver_tap+0x5be/0xc90 net/netlink/af_netlink.c:325
 netlink_deliver_tap net/netlink/af_netlink.c:338 [inline]
 netlink_deliver_tap_kernel net/netlink/af_netlink.c:347 [inline]
 netlink_unicast_kernel net/netlink/af_netlink.c:1341 [inline]
 netlink_unicast+0x10f1/0x1250 net/netlink/af_netlink.c:1368
 netlink_sendmsg+0x1238/0x13d0 net/netlink/af_netlink.c:1910
 sock_sendmsg_nosec net/socket.c:730 [inline]
 __sock_sendmsg net/socket.c:745 [inline]
 ____sys_sendmsg+0x9c2/0xd60 net/socket.c:2584
 ___sys_sendmsg+0x28d/0x3c0 net/socket.c:2638
 __sys_sendmsg net/socket.c:2667 [inline]
 __do_sys_sendmsg net/socket.c:2676 [inline]
 __se_sys_sendmsg net/socket.c:2674 [inline]
 __x64_sys_sendmsg+0x307/0x490 net/socket.c:2674
 do_syscall_x64 arch/x86/entry/common.c:52 [inline]
 do_syscall_64+0x44/0x110 arch/x86/entry/common.c:83
 entry_SYSCALL_64_after_hwframe+0x63/0x6b

Uninit was created at:
 free_pages_prepare mm/page_alloc.c:1087 [inline]
 free_unref_page_prepare+0xb0/0xa40 mm/page_alloc.c:2347
 free_unref_page_list+0xeb/0x1100 mm/page_alloc.c:2533
 release_pages+0x23d3/0x2410 mm/swap.c:1042
 free_pages_and_swap_cache+0xd9/0xf0 mm/swap_state.c:316
 tlb_batch_pages_flush mm/mmu_gather.c:98 [inline]
 tlb_flush_mmu_free mm/mmu_gather.c:293 [inline]
 tlb_flush_mmu+0x6f5/0x980 mm/mmu_gather.c:300
 tlb_finish_mmu+0x101/0x260 mm/mmu_gather.c:392
 exit_mmap+0x49e/0xd30 mm/mmap.c:3321
 __mmput+0x13f/0x530 kernel/fork.c:1349
 mmput+0x8a/0xa0 kernel/fork.c:1371
 exit_mm+0x1b8/0x360 kernel/exit.c:567
 do_exit+0xd57/0x4080 kernel/exit.c:858
 do_group_exit+0x2fd/0x390 kernel/exit.c:1021
 __do_sys_exit_group kernel/exit.c:1032 [inline]
 __se_sys_exit_group kernel/exit.c:1030 [inline]
 __x64_sys_exit_group+0x3c/0x50 kernel/exit.c:1030
 do_syscall_x64 arch/x86/entry/common.c:52 [inline]
 do_syscall_64+0x44/0x110 arch/x86/entry/common.c:83
 entry_SYSCALL_64_after_hwframe+0x63/0x6b

Bytes 3852-3903 of 3904 are uninitialized
Memory access of size 3904 starts at ffff88812ea1e000
Data copied to user address 0000000020003280

CPU: 1 PID: 5043 Comm: syz-executor297 Not tainted 6.7.0-rc5-syzkaller-00047-g5bd7ef53ffe5 #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 11/10/2023

Fixes: 1853c94964 ("netlink, mmap: transform mmap skb into full skb on taps")
Reported-and-tested-by: syzbot+34ad5fab48f7bf510349@syzkaller.appspotmail.com
Closes: https://syzkaller.appspot.com/bug?extid=34ad5fab48f7bf510349 [1]
Signed-off-by: Ryosuke Yasuoka <ryasuoka@redhat.com>
Reviewed-by: Eric Dumazet <edumazet@google.com>
Link: https://lore.kernel.org/r/20240221074053.1794118-1-ryasuoka@redhat.com
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
2024-02-22 18:56:09 -08:00
Colin Ian King
cbe30f9943 net: microchip: lan743x: Fix spelling mistake "erro" -> "error"
There is a spelling mistake in a netif_err message. Fix it.

Signed-off-by: Colin Ian King <colin.i.king@gmail.com>
Reviewed-by: Simon Horman <horms@kernel.org>
Link: https://lore.kernel.org/r/20240220091737.2676984-1-colin.i.king@gmail.com
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
2024-02-22 18:54:07 -08:00
Alexander Gordeev
9eda38dc91 net/af_iucv: fix virtual vs physical address confusion
Fix virtual vs physical address confusion. This does not fix a bug
since virtual and physical address spaces are currently the same.

Signed-off-by: Alexander Gordeev <agordeev@linux.ibm.com>
Reviewed-by: Alexandra Winter <wintera@linux.ibm.com>
Link: https://lore.kernel.org/r/20240215080500.2616848-1-agordeev@linux.ibm.com
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
2024-02-22 18:28:13 -08:00
Florian Fainelli
c2f0961a45 MAINTAINERS: Update SCMI entry with HWMON driver
scmi-hwmon.c is tightly coupled with the SCMI subsystem, fold it under
the SCMI subsystem MAINTAINERS umbrella.

Signed-off-by: Florian Fainelli <florian.fainelli@broadcom.com>
Link: https://lore.kernel.org/r/20240222193027.920006-1-florian.fainelli@broadcom.com
Signed-off-by: Sudeep Holla <sudeep.holla@arm.com>
2024-02-23 02:01:13 +00:00
Fabio Estevam
2b0a5a8a39 ARM: imx_v6_v7_defconfig: Restore CONFIG_BACKLIGHT_CLASS_DEVICE
Since commit bfac19e239 ("fbdev: mx3fb: Remove the driver") backlight
is no longer functional.

The fbdev mx3fb driver used to automatically select
CONFIG_BACKLIGHT_CLASS_DEVICE.

Now that the mx3fb driver has been removed, enable the
CONFIG_BACKLIGHT_CLASS_DEVICE option so that backlight can still work
by default.

Tested on a imx6dl-sabresd board.

Cc: stable@vger.kernel.org
Fixes: bfac19e239 ("fbdev: mx3fb: Remove the driver")
Signed-off-by: Fabio Estevam <festevam@denx.de>
Reviewed-by: Francesco Dolcini <francesco.dolcini@toradex.com>
Tested-by: Francesco Dolcini <francesco.dolcini@toradex.com> # Toradex Colibri iMX7
Signed-off-by: Shawn Guo <shawnguo@kernel.org>
2024-02-23 09:58:39 +08:00
Frank Li
c123e12f0a arm64: dts: imx8dxl update edma0 information
edma0 of iMX8DXL is difference with other imx8 chips. Update register's
size, channel number and power-domain.
Update i2c[0-3] channel number information.

Signed-off-by: Frank Li <Frank.Li@nxp.com>
Signed-off-by: Shawn Guo <shawnguo@kernel.org>
2024-02-23 09:56:13 +08:00
Frank Li
689feeed03 arm64: dts: imx8dxl: add fsl-dma.h dt-binding header file
Add fsl-dma.h dt-binding header file in imx8dxl chip dtsi file.

Signed-off-by: Frank Li <Frank.Li@nxp.com>
Signed-off-by: Shawn Guo <shawnguo@kernel.org>
2024-02-23 09:56:00 +08:00
Benjamin Tissoires
2ab256e932 bpf: add is_async_callback_calling_insn() helper
Currently we have a special case for BPF_FUNC_timer_set_callback,
let's introduce a helper we can extend for the kfunc that will come in
a later patch

Signed-off-by: Benjamin Tissoires <bentiss@kernel.org>
Link: https://lore.kernel.org/r/20240221-hid-bpf-sleepable-v3-3-1fb378ca6301@kernel.org
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
2024-02-22 17:48:53 -08:00
Benjamin Tissoires
dfe6625df4 bpf: introduce in_sleepable() helper
No code change, but it'll allow to have only one place to change
everything when we add in_sleepable in cur_state.

Signed-off-by: Benjamin Tissoires <bentiss@kernel.org>
Link: https://lore.kernel.org/r/20240221-hid-bpf-sleepable-v3-2-1fb378ca6301@kernel.org
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
2024-02-22 17:47:15 -08:00
Benjamin Tissoires
55bad79e33 bpf: allow more maps in sleepable bpf programs
These 2 maps types are required for HID-BPF when a user wants to do
IO with a device from a sleepable tracing point.

Allowing BPF_MAP_TYPE_QUEUE (and therefore BPF_MAP_TYPE_STACK) allows
for a BPF program to prepare from an IRQ the list of HID commands to send
back to the device and then these commands can be retrieved from the
sleepable trace point.

Signed-off-by: Benjamin Tissoires <bentiss@kernel.org>
Link: https://lore.kernel.org/r/20240221-hid-bpf-sleepable-v3-1-1fb378ca6301@kernel.org
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
2024-02-22 17:42:23 -08:00
Sean Christopherson
2dfd238303 KVM: selftests: Add a testcase to verify GUEST_MEMFD and READONLY are exclusive
Extend set_memory_region_test's invalid flags subtest to verify that
GUEST_MEMFD is incompatible with READONLY.  GUEST_MEMFD doesn't currently
support writes from userspace and KVM doesn't support emulated MMIO on
private accesses, and so KVM is supposed to reject the GUEST_MEMFD+READONLY
in order to avoid configuration that KVM can't support.

Link: https://lore.kernel.org/r/20240222190612.2942589-6-seanjc@google.com
Signed-off-by: Sean Christopherson <seanjc@google.com>
2024-02-22 17:07:06 -08:00
Sean Christopherson
63e5c5a105 KVM: selftests: Create GUEST_MEMFD for relevant invalid flags testcases
Actually create a GUEST_MEMFD instance and pass it to KVM when doing
negative tests for KVM_SET_USER_MEMORY_REGION2 + KVM_MEM_GUEST_MEMFD.
Without a valid GUEST_MEMFD file descriptor, KVM_SET_USER_MEMORY_REGION2
will always fail with -EINVAL, resulting in false passes for any and all
tests of illegal combinations of KVM_MEM_GUEST_MEMFD and other flags.

Fixes: 5d74316466 ("KVM: selftests: Add a memory region subtest to validate invalid flags")
Link: https://lore.kernel.org/r/20240222190612.2942589-5-seanjc@google.com
Signed-off-by: Sean Christopherson <seanjc@google.com>
2024-02-22 17:07:06 -08:00
Sean Christopherson
a1176ef5c9 KVM: x86/mmu: Restrict KVM_SW_PROTECTED_VM to the TDP MMU
Advertise and support software-protected VMs if and only if the TDP MMU is
enabled, i.e. disallow KVM_SW_PROTECTED_VM if TDP is enabled for KVM's
legacy/shadow MMU.  TDP support for the shadow MMU is maintenance-only,
e.g. support for TDX and SNP will also be restricted to the TDP MMU.

Fixes: 89ea60c2c7 ("KVM: x86: Add support for "protected VMs" that can utilize private memory")
Link: https://lore.kernel.org/r/20240222190612.2942589-4-seanjc@google.com
Signed-off-by: Sean Christopherson <seanjc@google.com>
2024-02-22 17:07:06 -08:00
Sean Christopherson
422692098c KVM: x86: Update KVM_SW_PROTECTED_VM docs to make it clear they're a WIP
Rewrite the help message for KVM_SW_PROTECTED_VM to make it clear that
software-protected VMs are a development and testing vehicle for
guest_memfd(), and that attempting to use KVM_SW_PROTECTED_VM for anything
remotely resembling a "real" VM will fail.  E.g. any memory accesses from
KVM will incorrectly access shared memory, nested TDP is wildly broken,
and so on and so forth.

Update KVM's API documentation with similar warnings to discourage anyone
from attempting to run anything but selftests with KVM_X86_SW_PROTECTED_VM.

Fixes: 89ea60c2c7 ("KVM: x86: Add support for "protected VMs" that can utilize private memory")
Link: https://lore.kernel.org/r/20240222190612.2942589-3-seanjc@google.com
Signed-off-by: Sean Christopherson <seanjc@google.com>
2024-02-22 17:07:06 -08:00
Sean Christopherson
e563592224 KVM: Make KVM_MEM_GUEST_MEMFD mutually exclusive with KVM_MEM_READONLY
Disallow creating read-only memslots that support GUEST_MEMFD, as
GUEST_MEMFD is fundamentally incompatible with KVM's semantics for
read-only memslots.  Read-only memslots allow the userspace VMM to emulate
option ROMs by filling the backing memory with readable, executable code
and data, while triggering emulated MMIO on writes.  GUEST_MEMFD doesn't
currently support writes from userspace and KVM doesn't support emulated
MMIO on private accesses, i.e. the guest can only ever read zeros, and
writes will always be treated as errors.

Cc: Fuad Tabba <tabba@google.com>
Cc: Michael Roth <michael.roth@amd.com>
Cc: Isaku Yamahata <isaku.yamahata@gmail.com>
Cc: Yu Zhang <yu.c.zhang@linux.intel.com>
Cc: Chao Peng <chao.p.peng@linux.intel.com>
Fixes: a7800aa80e ("KVM: Add KVM_CREATE_GUEST_MEMFD ioctl() for guest-specific backing memory")
Link: https://lore.kernel.org/r/20240222190612.2942589-2-seanjc@google.com
Signed-off-by: Sean Christopherson <seanjc@google.com>
2024-02-22 17:07:06 -08:00
Arnd Bergmann
ea3689d9df KVM: fix kvm_mmu_memory_cache allocation warning
gcc-14 notices that the arguments to kvmalloc_array() are mixed up:

arch/x86/kvm/../../../virt/kvm/kvm_main.c: In function '__kvm_mmu_topup_memory_cache':
arch/x86/kvm/../../../virt/kvm/kvm_main.c:424:53: error: 'kvmalloc_array' sizes specified with 'sizeof' in the earlier argument and not in the later argument [-Werror=calloc-transposed-args]
  424 |                 mc->objects = kvmalloc_array(sizeof(void *), capacity, gfp);
      |                                                     ^~~~
arch/x86/kvm/../../../virt/kvm/kvm_main.c:424:53: note: earlier argument should specify number of elements, later size of each element

The code still works correctly, but the incorrect order prevents the compiler
from properly tracking the object sizes.

Fixes: 837f66c712 ("KVM: Allow for different capacities in kvm_mmu_memory_cache structs")
Signed-off-by: Arnd Bergmann <arnd@arndb.de>
Reviewed-by: Marc Zyngier <maz@kernel.org>
Link: https://lore.kernel.org/r/20240212112419.1186065-1-arnd@kernel.org
Signed-off-by: Sean Christopherson <seanjc@google.com>
2024-02-22 17:02:26 -08:00
Andy Shevchenko
fd8ed16c24 bitmap: Step down as a reviewer
Too many things are going on, and reviewing BITMAP related code
seems not the best I can do, hence step down as a reviewer of
the BITMAP library.

Signed-off-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com>
Signed-off-by: Yury Norov <yury.norov@gmail.com>
2024-02-22 16:33:30 -08:00
Sean Christopherson
576a15de8d KVM: x86/mmu: Free TDP MMU roots while holding mmy_lock for read
Free TDP MMU roots from vCPU context while holding mmu_lock for read, it
is completely legal to invoke kvm_tdp_mmu_put_root() as a reader.  This
eliminates the last mmu_lock writer in the TDP MMU's "fast zap" path
after requesting vCPUs to reload roots, i.e. allows KVM to zap invalidated
roots, free obsolete roots, and allocate new roots in parallel.

On large VMs, e.g. 100+ vCPUs, allowing the bulk of the "fast zap"
operation to run in parallel with freeing and allocating roots reduces the
worst case latency for a vCPU to reload a root from 2-3ms to <100us.

Link: https://lore.kernel.org/r/20240111020048.844847-9-seanjc@google.com
Signed-off-by: Sean Christopherson <seanjc@google.com>
2024-02-22 16:28:45 -08:00
Sean Christopherson
dab285e4ec KVM: x86/mmu: Alloc TDP MMU roots while holding mmu_lock for read
Allocate TDP MMU roots while holding mmu_lock for read, and instead use
tdp_mmu_pages_lock to guard against duplicate roots.  This allows KVM to
create new roots without forcing kvm_tdp_mmu_zap_invalidated_roots() to
yield, e.g. allows vCPUs to load new roots after memslot deletion without
forcing the zap thread to detect contention and yield (or complete if the
kernel isn't preemptible).

Note, creating a new TDP MMU root as an mmu_lock reader is safe for two
reasons: (1) paths that must guarantee all roots/SPTEs are *visited* take
mmu_lock for write and so are still mutually exclusive, e.g. mmu_notifier
invalidations, and (2) paths that require all roots/SPTEs to *observe*
some given state without holding mmu_lock for write must ensure freshness
through some other means, e.g. toggling dirty logging must first wait for
SRCU readers to recognize the memslot flags change before processing
existing roots/SPTEs.

Link: https://lore.kernel.org/r/20240111020048.844847-8-seanjc@google.com
Signed-off-by: Sean Christopherson <seanjc@google.com>
2024-02-22 16:28:45 -08:00
Sean Christopherson
f5238c2a60 KVM: x86/mmu: Check for usable TDP MMU root while holding mmu_lock for read
When allocating a new TDP MMU root, check for a usable root while holding
mmu_lock for read and only acquire mmu_lock for write if a new root needs
to be created.  There is no need to serialize other MMU operations if a
vCPU is simply grabbing a reference to an existing root, holding mmu_lock
for write is "necessary" (spoiler alert, it's not strictly necessary) only
to ensure KVM doesn't end up with duplicate roots.

Allowing vCPUs to get "new" roots in parallel is beneficial to VM boot and
to setups that frequently delete memslots, i.e. which force all vCPUs to
reload all roots.

Link: https://lore.kernel.org/r/20240111020048.844847-7-seanjc@google.com
Signed-off-by: Sean Christopherson <seanjc@google.com>
2024-02-22 16:28:45 -08:00
Sean Christopherson
d746182337 KVM: x86/mmu: Skip invalid TDP MMU roots when write-protecting SPTEs
When write-protecting SPTEs, don't process invalid roots as invalid roots
are unreachable, i.e. can't be used to access guest memory and thus don't
need to be write-protected.

Note, this is *almost* a nop for kvm_tdp_mmu_clear_dirty_pt_masked(),
which is called under slots_lock, i.e. is mutually exclusive with
kvm_mmu_zap_all_fast().  But it's possible for something other than the
"fast zap" thread to grab a reference to an invalid root and thus keep a
root alive (but completely empty) after kvm_mmu_zap_all_fast() completes.

The kvm_tdp_mmu_write_protect_gfn() case is more interesting as KVM write-
protects SPTEs for reasons other than dirty logging, e.g. if a KVM creates
a SPTE for a nested VM while a fast zap is in-progress.

Add another TDP MMU iterator to visit only valid roots, and
opportunistically convert kvm_tdp_mmu_get_vcpu_root_hpa() to said iterator.

Link: https://lore.kernel.org/r/20240111020048.844847-6-seanjc@google.com
Signed-off-by: Sean Christopherson <seanjc@google.com>
2024-02-22 16:28:45 -08:00
Sean Christopherson
99b85fda91 KVM: x86/mmu: Skip invalid roots when zapping leaf SPTEs for GFN range
When zapping a GFN in response to an APICv or MTRR change, don't zap SPTEs
for invalid roots as KVM only needs to ensure the guest can't use stale
mappings for the GFN.  Unlike kvm_tdp_mmu_unmap_gfn_range(), which must
zap "unreachable" SPTEs to ensure KVM doesn't mark a page accessed/dirty,
kvm_tdp_mmu_zap_leafs() isn't used (and isn't intended to be used) to
handle freeing of host memory.

Link: https://lore.kernel.org/r/20240111020048.844847-5-seanjc@google.com
Signed-off-by: Sean Christopherson <seanjc@google.com>
2024-02-22 16:28:45 -08:00
Sean Christopherson
6577f1efdf KVM: x86/mmu: Allow passing '-1' for "all" as_id for TDP MMU iterators
Modify for_each_tdp_mmu_root() and __for_each_tdp_mmu_root_yield_safe() to
accept -1 for _as_id to mean "process all memslot address spaces".  That
way code that wants to process both SMM and !SMM doesn't need to iterate
over roots twice (and likely copy+paste code in the process).

Deliberately don't cast _as_id to an "int", just in case not casting helps
the compiler elide the "_as_id >=0" check when being passed an unsigned
value, e.g. from a memslot.

No functional change intended.

Link: https://lore.kernel.org/r/20240111020048.844847-4-seanjc@google.com
Signed-off-by: Sean Christopherson <seanjc@google.com>
2024-02-22 16:28:45 -08:00
Sean Christopherson
fcdffe97f8 KVM: x86/mmu: Don't do TLB flush when zappings SPTEs in invalid roots
Don't force a TLB flush when zapping SPTEs in invalid roots as vCPUs
can't be actively using invalid roots (zapping SPTEs in invalid roots is
necessary only to ensure KVM doesn't mark a page accessed/dirty after it
is freed by the primary MMU).

Link: https://lore.kernel.org/r/20240111020048.844847-3-seanjc@google.com
Signed-off-by: Sean Christopherson <seanjc@google.com>
2024-02-22 16:28:45 -08:00
Sean Christopherson
8ca983631f KVM: x86/mmu: Zap invalidated TDP MMU roots at 4KiB granularity
Zap invalidated TDP MMU roots at maximum granularity, i.e. with more
frequent conditional resched checkpoints, in order to avoid running for an
extended duration (milliseconds, or worse) without honoring a reschedule
request.  And for kernels running with full or real-time preempt models,
zapping at 4KiB granularity also provides significantly reduced latency
for other tasks that are contending for mmu_lock (which isn't necessarily
an overall win for KVM, but KVM should do its best to honor the kernel's
preemption model).

To keep KVM's assertion that zapping at 1GiB granularity is functionally
ok, which is the main reason 1GiB was selected in the past, skip straight
to zapping at 1GiB if KVM is configured to prove the MMU.  Zapping roots
is far more common than a vCPU replacing a 1GiB page table with a hugepage,
e.g. generally happens multiple times during boot, and so keeping the test
coverage provided by root zaps is desirable, just not for production.

Cc: David Matlack <dmatlack@google.com>
Cc: Pattara Teerapong <pteerapong@google.com>
Link: https://lore.kernel.org/r/20240111020048.844847-2-seanjc@google.com
Signed-off-by: Sean Christopherson <seanjc@google.com>
2024-02-22 16:28:45 -08:00
Sean Christopherson
dafc17dd52 KVM: Add a comment explaining the directed yield pending interrupt logic
Add a comment to explain why KVM treats vCPUs with pending interrupts as
in-kernel when a vCPU wants to yield to a vCPU that was preempted while
running in kernel mode.

Link: https://lore.kernel.org/r/20240110003938.490206-5-seanjc@google.com
Signed-off-by: Sean Christopherson <seanjc@google.com>
2024-02-22 16:27:41 -08:00
Sean Christopherson
322d79f1db KVM: x86: Clean up directed yield API for "has pending interrupt"
Directly return the boolean result of whether or not a vCPU has a pending
interrupt instead of effectively doing:

  if (true)
	return true;

  return false;

Reviewed-by: Yuan Yao <yuan.yao@intel.com>
Link: https://lore.kernel.org/r/20240110003938.490206-4-seanjc@google.com
Signed-off-by: Sean Christopherson <seanjc@google.com>
2024-02-22 16:27:40 -08:00
Sean Christopherson
9b8615c5d3 KVM: x86: Rely solely on preempted_in_kernel flag for directed yield
Snapshot preempted_in_kernel using kvm_arch_vcpu_in_kernel() so that the
flag is "accurate" (or rather, consistent and deterministic within KVM)
for guests with protected state, and explicitly use preempted_in_kernel
when checking if a vCPU was preempted in kernel mode instead of bouncing
through kvm_arch_vcpu_in_kernel().

Drop the gnarly logic in kvm_arch_vcpu_in_kernel() that redirects to
preempted_in_kernel if the target vCPU is not the "running", i.e. loaded,
vCPU, as the only reason that code existed was for the directed yield case
where KVM wants to check the CPL of a vCPU that may or may not be loaded
on the current pCPU.

Cc: Like Xu <like.xu.linux@gmail.com>
Reviewed-by: Yuan Yao <yuan.yao@intel.com>
Link: https://lore.kernel.org/r/20240110003938.490206-3-seanjc@google.com
Signed-off-by: Sean Christopherson <seanjc@google.com>
2024-02-22 16:27:03 -08:00
Sean Christopherson
77bcd9e623 KVM: Add dedicated arch hook for querying if vCPU was preempted in-kernel
Plumb in a dedicated hook for querying whether or not a vCPU was preempted
in-kernel.  Unlike literally every other architecture, x86's VMX can check
if a vCPU is in kernel context if and only if the vCPU is loaded on the
current pCPU.

x86's kvm_arch_vcpu_in_kernel() works around the limitation by querying
kvm_get_running_vcpu() and redirecting to vcpu->arch.preempted_in_kernel
as needed.  But that's unnecessary, confusing, and fragile, e.g. x86 has
had at least one bug where KVM incorrectly used a stale
preempted_in_kernel.

No functional change intended.

Reviewed-by: Yuan Yao <yuan.yao@intel.com>
Link: https://lore.kernel.org/r/20240110003938.490206-2-seanjc@google.com
Signed-off-by: Sean Christopherson <seanjc@google.com>
2024-02-22 16:26:26 -08:00
Sean Christopherson
fc3c94142b KVM: x86: Sanity check that kvm_has_noapic_vcpu is zero at module_exit()
WARN if kvm.ko is unloaded with an elevated kvm_has_noapic_vcpu to guard
against incorrect management of the key, e.g. to detect if KVM fails to
decrement the key in error paths.  Because kvm_has_noapic_vcpu is purely
an optimization, in all likelihood KVM could completely botch handling of
kvm_has_noapic_vcpu and no one would notice (which is a good argument for
deleting the key entirely, but that's a problem for another day).

Note, ideally the sanity check would be performance when kvm_usage_count
goes to zero, but adding an arch callback just for this sanity check isn't
at all worth doing.

Link: https://lore.kernel.org/r/20240209222047.394389-3-seanjc@google.com
Signed-off-by: Sean Christopherson <seanjc@google.com>
2024-02-22 16:24:26 -08:00
Sean Christopherson
a78d904669 KVM: x86: Move "KVM no-APIC vCPU" key management into local APIC code
Move incrementing and decrementing of kvm_has_noapic_vcpu into
kvm_create_lapic() and kvm_free_lapic() respectively to fix a benign bug
where KVM fails to decrement the count if vCPU creation ultimately fails,
e.g. due to a memory allocation failing.

Note, the bug is benign as kvm_has_noapic_vcpu is used purely to optimize
lapic_in_kernel() checks, and that optimization is quite dubious.  That,
and practically speaking no setup that cares at all about performance runs
with a userspace local APIC.

Reported-by: Li RongQing <lirongqing@baidu.com>
Cc: Maxim Levitsky <mlevitsk@redhat.com>
Reviewed-by: Xu Yilun <yilun.xu@linux.intel.com>
Link: https://lore.kernel.org/r/20240209222047.394389-2-seanjc@google.com
Signed-off-by: Sean Christopherson <seanjc@google.com>
2024-02-22 16:24:09 -08:00
Sean Christopherson
0ec3d6d1f1 KVM: x86: Fully defer to vendor code to decide how to force immediate exit
Now that vmx->req_immediate_exit is used only in the scope of
vmx_vcpu_run(), use force_immediate_exit to detect that KVM should usurp
the VMX preemption to force a VM-Exit and let vendor code fully handle
forcing a VM-Exit.

Opportunsitically drop __kvm_request_immediate_exit() and just have
vendor code call smp_send_reschedule() directly.  SVM already does this
when injecting an event while also trying to single-step an IRET, i.e.
it's not exactly secret knowledge that KVM uses a reschedule IPI to force
an exit.

Link: https://lore.kernel.org/r/20240110012705.506918-7-seanjc@google.com
Signed-off-by: Sean Christopherson <seanjc@google.com>
2024-02-22 16:22:41 -08:00
Sean Christopherson
7b3d1bbf8d KVM: VMX: Handle KVM-induced preemption timer exits in fastpath for L2
Eat VMX treemption timer exits in the fastpath regardless of whether L1 or
L2 is active.  The VM-Exit is 100% KVM-induced, i.e. there is nothing
directly related to the exit that KVM needs to do on behalf of the guest,
thus there is no reason to wait until the slow path to do nothing.

Opportunistically add comments explaining why preemption timer exits for
emulating the guest's APIC timer need to go down the slow path.

Link: https://lore.kernel.org/r/20240110012705.506918-6-seanjc@google.com
Signed-off-by: Sean Christopherson <seanjc@google.com>
2024-02-22 16:22:37 -08:00
Sean Christopherson
bf1a49436e KVM: x86: Move handling of is_guest_mode() into fastpath exit handlers
Let the fastpath code decide which exits can/can't be handled in the
fastpath when L2 is active, e.g. when KVM generates a VMX preemption
timer exit to forcefully regain control, there is no "work" to be done and
so such exits can be handled in the fastpath regardless of whether L1 or
L2 is active.

Moving the is_guest_mode() check into the fastpath code also makes it
easier to see that L2 isn't allowed to use the fastpath in most cases,
e.g. it's not immediately obvious why handle_fastpath_preemption_timer()
is called from the fastpath and the normal path.

Link: https://lore.kernel.org/r/20240110012705.506918-5-seanjc@google.com
Signed-off-by: Sean Christopherson <seanjc@google.com>
2024-02-22 16:22:36 -08:00
Sean Christopherson
11776aa0cf KVM: VMX: Handle forced exit due to preemption timer in fastpath
Handle VMX preemption timer VM-Exits due to KVM forcing an exit in the
exit fastpath, i.e. avoid calling back into handle_preemption_timer() for
the same exit.  There is no work to be done for forced exits, as the name
suggests the goal is purely to get control back in KVM.

In addition to shaving a few cycles, this will allow cleanly separating
handle_fastpath_preemption_timer() from handle_preemption_timer(), e.g.
it's not immediately obvious why _apparently_ calling
handle_fastpath_preemption_timer() twice on a "slow" exit is necessary:
the "slow" call is necessary to handle exits from L2, which are excluded
from the fastpath by vmx_vcpu_run().

Link: https://lore.kernel.org/r/20240110012705.506918-4-seanjc@google.com
Signed-off-by: Sean Christopherson <seanjc@google.com>
2024-02-22 16:22:36 -08:00
Sean Christopherson
e6b5d16bbd KVM: VMX: Re-enter guest in fastpath for "spurious" preemption timer exits
Re-enter the guest in the fast path if VMX preeemption timer VM-Exit was
"spurious", i.e. if KVM "soft disabled" the timer by writing -1u and by
some miracle the timer expired before any other VM-Exit occurred.  This is
just an intermediate step to cleaning up the preemption timer handling,
optimizing these types of spurious VM-Exits is not interesting as they are
extremely rare/infrequent.

Link: https://lore.kernel.org/r/20240110012705.506918-3-seanjc@google.com
Signed-off-by: Sean Christopherson <seanjc@google.com>
2024-02-22 16:22:36 -08:00
Sean Christopherson
9c9025ea00 KVM: x86: Plumb "force_immediate_exit" into kvm_entry() tracepoint
Annotate the kvm_entry() tracepoint with "immediate exit" when KVM is
forcing a VM-Exit immediately after VM-Enter, e.g. when KVM wants to
inject an event but needs to first complete some other operation.
Knowing that KVM is (or isn't) forcing an exit is useful information when
debugging issues related to event injection.

Suggested-by: Maxim Levitsky <mlevitsk@redhat.com>
Link: https://lore.kernel.org/r/20240110012705.506918-2-seanjc@google.com
Signed-off-by: Sean Christopherson <seanjc@google.com>
2024-02-22 16:22:36 -08:00