Wrap the io_ring_head_to_buf() macro value in an extra pair of parentheses
so it is safe when composed into larger expressions, and to satisfy
scripts/checkpatch.pl.
Signed-off-by: Yi Xie <xieyi@kylinos.cn>
Link: https://patch.msgid.link/20260514083443.203387-1-xieyi@kylinos.cn
Signed-off-by: Jens Axboe <axboe@kernel.dk>
At this time the driver is not listing any speeds
it supports. This should be ETHTOOL_LINK_MODE_100baseT1_Full_BIT
for DP83TC811. Add the missing call for phylib to read the abilities.
Fixes: b753a9faaf ("net: phy: DP83TC811: Introduce support for the DP83TC811 phy")
Suggested-by: Andrew Lunn <andrew@lunn.ch>
Signed-off-by: Sven Schuchmann <schuchmann@schleissheimer.de>
Reviewed-by: Andrew Lunn <andrew@lunn.ch>
Link: https://patch.msgid.link/20260512071949.6218-1-schuchmann@schleissheimer.de
[pabeni@redhat.com: dropped revision history]
Signed-off-by: Paolo Abeni <pabeni@redhat.com>
flush_rcu_sheaves_on_cache() calls queue_work_on() in a
for_each_online_cpu() loop, which requires the cpu to stay online.
But cpus_read_lock() is not held in kvfree_rcu_barrier_on_cache() and the
set of "online cpus" is subject to change.
There are two paths that call flush_rcu_sheaves_on_cache():
// has cpus_read_lock()
flush_all_rcu_sheaves()
-> flush_rcu_sheaves_on_cache()
// no cpus_read_lock()
kvfree_rcu_barrier_on_cache()
-> flush_rcu_sheaves_on_cache()
Fix this by holding cpus_read_lock() in kvfree_rcu_barrier_on_cache().
Why not move cpus_read_lock() from flush_all_rcu_sheaves() into
flush_rcu_sheaves_on_cache()? The reason is it would introduce a new lock
order (slab_mutex -> cpu_hotplug_lock). The reverse order
(cpu_hotplug_lock -> slab_mutex) is established by
- cpuhp_setup_state_nocalls(..., slub_cpu_setup, ...)
- kmem_cache_destroy()
The two orders together would form an AB-BA deadlock.
Finally, add lockdep_assert_cpus_held() in flush_rcu_sheaves_on_cache()
to catch the same problem in the future.
Fixes: 0f35040de5 ("mm/slab: introduce kvfree_rcu_barrier_on_cache() for cache destruction")
Cc: <stable@vger.kernel.org>
Signed-off-by: Qing Wang <wangqing7171@gmail.com>
Link: https://patch.msgid.link/20260512035035.762317-1-wangqing7171@gmail.com
Signed-off-by: Vlastimil Babka (SUSE) <vbabka@kernel.org>
The unstripped vDSO files are useful for debugging.
They are provided in the upstream 'linux-headers' package.
Also package them as part of 'make pacman-pkg'.
Make them part of the '-debug' package, as they fit there best.
This differs from the upstream package as that has no '-debug' variant.
Signed-off-by: Thomas Weißschuh <linux@weissschuh.net>
Reviewed-by: Nathan Chancellor <nathan@kernel.org>
Tested-by: Nathan Chancellor <nathan@kernel.org>
Link: https://patch.msgid.link/20260318-kbuild-pacman-vdso-install-v1-1-48ceb31c0e80@weissschuh.net
Signed-off-by: Nathan Chancellor <nathan@kernel.org>
Add a 'gpat' field to kvm_svm_nested_state_hdr to carry L2's guest PAT
value across save and restore.
When KVM_X86_QUIRK_NESTED_SVM_SHARED_PAT is disabled and the vCPU is in
guest mode with nested NPT enabled, save vmcb02's g_pat into the header on
KVM_GET_NESTED_STATE, and restore it on KVM_SET_NESTED_STATE.
Host-initiated accesses to IA32_PAT (via KVM_GET/SET_MSRS) always target
L1's hPAT, so they cannot be used to save or restore gPAT. The separate
header field ensures that KVM_GET/SET_MSRS and KVM_GET/SET_NESTED_STATE are
independent and can be ordered arbitrarily during save and restore.
Note that struct kvm_svm_nested_state_hdr is included in a union padded to
120 bytes, so there is room to add the gpat field without changing any
offsets.
Fixes: cc440cdad5 ("KVM: nSVM: implement KVM_GET_NESTED_STATE and KVM_SET_NESTED_STATE")
Signed-off-by: Jim Mattson <jmattson@google.com>
Link: https://patch.msgid.link/20260407190343.325299-9-jmattson@google.com
Signed-off-by: Sean Christopherson <seanjc@google.com>
Document the nested state constants and structures for SVM that were added
by commit cc440cdad5 ("KVM: nSVM: implement KVM_GET_NESTED_STATE and
KVM_SET_NESTED_STATE").
Fixes: cc440cdad5 ("KVM: nSVM: implement KVM_GET_NESTED_STATE and KVM_SET_NESTED_STATE")
Signed-off-by: Jim Mattson <jmattson@google.com>
Link: https://patch.msgid.link/20260407190343.325299-8-jmattson@google.com
Signed-off-by: Sean Christopherson <seanjc@google.com>
According to the APM volume 3 pseudo-code for "VMRUN," when nested paging
is enabled in the vmcb, the guest PAT register (gPAT) is saved to the vmcb
on emulated VMEXIT.
When KVM_X86_QUIRK_NESTED_SVM_SHARED_PAT is disabled and the vCPU is in
guest mode with nested NPT enabled, save the vmcb02 g_pat field to the
vmcb12 g_pat field on emulated VMEXIT.
Fixes: 15038e1472 ("KVM: SVM: obey guest PAT")
Signed-off-by: Jim Mattson <jmattson@google.com>
Link: https://patch.msgid.link/20260407190343.325299-7-jmattson@google.com
Signed-off-by: Sean Christopherson <seanjc@google.com>
When handling PAT accesses from L2, route PAT accesses to either hPAT or
gPAT based on whether or not L2 has a separate PAT, i.e. if KVM is actually
emulating gPAT, instead of using L1's PAT for everything. Specifically, if
KVM_X86_QUIRK_NESTED_SVM_SHARED_PAT is disabled, the vCPU is in guest mode
with nested NPT enabled, *and* the access if from the guest (i.e. is not
from the host stuffing PAT as part of save/restore), then redirect guest
PAT accesses to the gPAT "register" in vmcb02, i.e. emulate gPAT for L2.
Always route non-guest accesses to hPAT, i.e. L1's PAT in vcpu->arch.pat,
to ensures that KVM_{G,S}ET_MSRS and KVM_{G,S}ET_NESTED_STATE are
independent of each other and can be ordered arbitrarily during save and
restore. E.g. if KVM didn't exempt host accesses, then whether a write to
PAT hit hPAT or gPAT would vary based on whether userspace restores PAT
before or after nested state. Note, gPAT is saved and restored separately
via KVM_{G,S}ET_NESTED_STATE.
WARN if there's a host-initiated access to PAT from within KVM_RUN, i.e. if
KVM itself initiated the access, as there are no such accesses today, and
it's not clear what the "right" behavior would be.
Fixes: 15038e1472 ("KVM: SVM: obey guest PAT")
Signed-off-by: Jim Mattson <jmattson@google.com>
Co-developed-by: Sean Christopherson <seanjc@google.com>
Signed-off-by: Sean Christopherson <seanjc@google.com>
When KVM_X86_QUIRK_NESTED_SVM_SHARED_PAT is disabled and nested NPT is
enabled in vmcb12, copy the (cached and validated) vmcb12 g_pat field to
vmcb02's g_pat, giving L2 its own independent guest PAT register.
When the quirk is enabled (default), or when NPT is enabled but nested NPT
is disabled, copy L1's IA32_PAT MSR to the vmcb02 g_pat field, since L2
shares the IA32_PAT MSR with L1.
When NPT is disabled, the g_pat field is ignored by hardware.
Fixes: 15038e1472 ("KVM: SVM: obey guest PAT")
Signed-off-by: Jim Mattson <jmattson@google.com>
Link: https://patch.msgid.link/20260407190343.325299-5-jmattson@google.com
Signed-off-by: Sean Christopherson <seanjc@google.com>
When KVM_X86_QUIRK_NESTED_SVM_SHARED_PAT is disabled and nested paging is
enabled in vmcb12, validate g_pat at emulated VMRUN and cause an immediate
VMEXIT with exit code VMEXIT_INVALID if it is invalid, as specified in the
APM, volume 2: "Nested Paging and VMRUN/VMEXIT."
Fixes: 3d6368ef58 ("KVM: SVM: Add VMRUN handler")
Signed-off-by: Jim Mattson <jmattson@google.com>
Link: https://patch.msgid.link/20260407190343.325299-4-jmattson@google.com
Signed-off-by: Sean Christopherson <seanjc@google.com>
When running an L2 guest and writing to MSR_IA32_CR_PAT, the host PAT value
is stored in both vmcb01's g_pat field and vmcb02's g_pat field, but the
clean bit was only being cleared for vmcb02.
Introduce the helper vmcb_set_gpat() which sets vmcb->save.g_pat and marks
the VMCB dirty for VMCB_NPT. Use this helper in both svm_set_msr() for
updating vmcb01 and in nested_vmcb02_compute_g_pat() for updating vmcb02,
ensuring both VMCBs' NPT fields are properly marked dirty.
Fixes: 4995a3685f ("KVM: SVM: Use a separate vmcb for the nested L2 guest")
Signed-off-by: Jim Mattson <jmattson@google.com>
Link: https://patch.msgid.link/20260407190343.325299-3-jmattson@google.com
Signed-off-by: Sean Christopherson <seanjc@google.com>
Define a quirk to control whether nested SVM shares L1's PAT with L2
(legacy behavior) or gives L2 its own independent gPAT (correct behavior
per the APM).
When the quirk is enabled (default), L2 shares L1's PAT, preserving the
legacy KVM behavior. When userspace disables the quirk, KVM correctly
virtualizes the PAT for nested SVM guests, giving L2 a separate gPAT as
specified in the AMD architecture.
Signed-off-by: Jim Mattson <jmattson@google.com>
Link: https://patch.msgid.link/20260407190343.325299-2-jmattson@google.com
Signed-off-by: Sean Christopherson <seanjc@google.com>
The threat-model document says that only users with CAP_SYS_ADMIN can carry
out a number of admin-level tasks, but there are numerous capabilities that
can confer that sort of power. Generalize the text slightly to make it
clear that CAP_SYS_ADMIN is not the only all-powerful capability.
Acked-by: Willy Tarreau <w@1wt.eu>
Signed-off-by: Jonathan Corbet <corbet@lwn.net>
Rather than make readers search for this document, just a link to it where
it is referenced.
(While I was at it, I removed the unused and unneeded _threatmodel label
from the top of threat-model.rst).
Acked-by: Willy Tarreau <w@1wt.eu>
Reviewed-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Signed-off-by: Jonathan Corbet <corbet@lwn.net>
Increase the JFFS2 partition size to support larger root filesystem.
Also fix the partition label to match the actual start address.
Signed-off-by: Niravkumar L Rabara <niravkumar.l.rabara@altera.com>
Signed-off-by: Nazim Amirul <muhammad.nazim.amirul.nazle.asmade@altera.com>
Signed-off-by: Dinh Nguyen <dinguyen@kernel.org>
The capital letters are for symbols and N in 'default N' will be evaluated as
another, nonexistent, Kconfig symbol, and not as the 'no' it should be. More
importantly, 'n' *is* the default already. Hence just drop the malformed line.
Signed-off-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com>
Signed-off-by: Borislav Petkov (AMD) <bp@alien8.de>
Link: https://patch.msgid.link/20260513205021.368190-1-andriy.shevchenko@linux.intel.com
Sashiko points out that if end = 0 (start != 0) the current
code will create a chain link to content type right after
the wrap link:
This would create a chain where the wrap link points directly
to another chain link. The scatterlist API sg_next iterator
does not recursively resolve consecutive chain links.
meaning this is illegal input to crypto.
The wrapping link is unnecessary if end = 0. end is the entry after
the last one used so end = 0 means there's nothing pushed after
the wrap:
end start i
v v v
[ ]...[ ][ d ][ d ][ d ][ d ][rsv for wrap]
Skip the wrapping in this case.
TLS 1.3 can use the "wrapping slot" for it's chaining if end = 0.
This avoids the chain-after-chain.
Move the wrap chaining before marking END and chaining off content
type, that feels like more logical ordering to me, but should not
matter from functional perspective.
Reported-by: Sashiko <sashiko-bot@kernel.org>
Fixes: 9aaaa56845 ("bpf: Sockmap/tls, skmsg can have wrapped skmsg that needs extra chaining")
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
Link: https://patch.msgid.link/20260511174920.433155-3-kuba@kernel.org
Signed-off-by: Paolo Abeni <pabeni@redhat.com>
When an sk_msg scatterlist ring wraps (sg.end < sg.start),
tls_push_record() chains the tail portion of the ring to the head
using sg_chain(). An extra entry in the sg array is reserved for
this:
struct sk_msg_sg {
[...]
/* The extra two elements:
* 1) used for chaining the front and sections when the list becomes
* partitioned (e.g. end < start). The crypto APIs require the
* chaining;
* 2) to chain tailer SG entries after the message.
*/
struct scatterlist data[MAX_MSG_FRAGS + 2];
The current code uses MAX_SKB_FRAGS + 1 as the ring size:
sg_chain(&msg_pl->sg.data[msg_pl->sg.start],
MAX_SKB_FRAGS - msg_pl->sg.start + 1,
msg_pl->sg.data);
This places the chain pointer at
sg_chain(data[start], (MAX_SKB_FRAGS - msg_start + 1) .. =
&data[start] + (MAX_SKB_FRAGS - msg_start + 1) - 1 =
data[start + (MAX_SKB_FRAGS - start + 1) - 1] =
data[MAX_SKB_FRAGS]
instead of the true last entry. This is likely due to a "race" of
the commit under Fixes landing close to
commit 031097d9e0 ("bpf: sk_msg, zap ingress queue on psock down")
Convert to ARRAY_SIZE and drop the data[start] / - start (as suggested
by Sabrina).
Reported-by: 钱一铭 <yimingqian591@gmail.com>
Fixes: 9aaaa56845 ("bpf: Sockmap/tls, skmsg can have wrapped skmsg that needs extra chaining")
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
Reviewed-by: Sabrina Dubroca <sd@queasysnail.net>
Link: https://patch.msgid.link/20260511174920.433155-2-kuba@kernel.org
Signed-off-by: Paolo Abeni <pabeni@redhat.com>
SCPI clock providers are registered for each child node in
scpi_clk_add(), but scpi_clocks_remove() unregisters the parent node on
each iteration.
of_clk_del_provider() matches providers by the node used at registration
time, so passing the parent node leaves the child providers registered.
This leaks the provider allocations and the node references held by the
clock provider core.
Pass the child node to of_clk_del_provider() so the remove path matches
the probe path.
Fixes: cd52c2a4b5 ("clk: add support for clocks provided by SCP(System Control Processor)")
Signed-off-by: Stepan Ionichev <sozdayvek@gmail.com>
Link: https://patch.msgid.link/20260513090900.5323-1-sozdayvek@gmail.com
(sudeep.holla: Updated commit title and message a bit)
Signed-off-by: Sudeep Holla <sudeep.holla@kernel.org>
dmem_cgroup_try_charge() returns -EAGAIN when the cgroup limit is
hit and the charge fails. TTM has no concept of -EAGAIN from resource
allocation; -ENOSPC is the canonical error meaning "no space, try
eviction". Convert at the source in ttm_resource_alloc() so no caller
needs to handle an unexpected error code, and clean up the now-redundant
-EAGAIN check in ttm_bo_alloc_resource().
Without this, -EAGAIN escaping ttm_resource_alloc() during an eviction
walk causes the walk to terminate early instead of continuing to the
next candidate.
Cc: Friedrich Vock <friedrich.vock@gmx.de>
Cc: Maarten Lankhorst <dev@lankhorst.se>
Cc: Tejun Heo <tj@kernel.org>
Cc: Maxime Ripard <mripard@kernel.org>
Cc: Christian Koenig <christian.koenig@amd.com>
Cc: dri-devel@lists.freedesktop.org
Cc: <stable@vger.kernel.org> # v6.14+
Fixes: 2b624a2c18 ("drm/ttm: Handle cgroup based eviction in TTM")
Assisted-by: GitHub_Copilot:claude-sonnet-4.6
Signed-off-by: Thomas Hellström <thomas.hellstrom@linux.intel.com>
Reviewed-by: Maarten Lankhorst <dev@lankhrost.se>
Link: https://patch.msgid.link/20260508160920.230339-1-thomas.hellstrom@linux.intel.com
Danielle Ratson says:
====================
bridge: Add selective forwarding of gratuitous neighbor announcements
The existing neighbor suppression unconditionally suppresses gratuitous
ARPs and unsolicited Neighbor Advertisements, which prevents fast
mobility of hosts between VTEPs.
This series adds a new neigh_forward_grat option that provides
independent control of gratuitous ARP and unsolicited NA forwarding.
When neigh_suppress is enabled but neigh_forward_grat is enabled,
regular neighbor discovery is suppressed while gratuitous announcements
are forwarded.
The implementation marks gratuitous ARPs and unsolicited NAs in
BR_INPUT_SKB_CB during input processing, then checks the per-output-port
neigh_forward_grat setting during flooding. This allows gratuitous
announcements from any input port to be selectively forwarded based on
each output port's individual configuration.
Both port-level control (via IFLA_BRPORT_NEIGH_FORWARD_GRAT) and
per-VLAN control (via BRIDGE_VLANDB_ENTRY_NEIGH_FORWARD_GRAT) are
provided. The default value of OFF preserves existing behavior.
This behavior is in accordance with RFC 9161 (Section 3.6), which
recommends that VTEPs forward gratuitous ARP and unsolicited NA messages
to avoid traffic disruption during host mobility events.
The new attributes use NLA_U8, although the kernel netlink guideline
recommends NLA_U32 as the minimum integer type on the grounds that
alignment makes smaller types equivalent on the wire. For a simple
on/off attribute there is no technical advantage to u32 over u8, and
keeping u8 preserves consistency with all surrounding bridge port
attributes and avoids introducing new helpers alongside the existing
infrastructure.
Patchset overview:
Patch #1: adds uapi headers.
Patches #2-#3: support selective forwarding of gratuitous ARP.
Patches #4-#5: add netlink handling.
Patch #6: adds tests.
Please see iproute related patches in the last 3 commits of:
https://github.com/daniellerts/iproute2
====================
Link: https://patch.msgid.link/20260511065936.4173106-1-danieller@nvidia.com
Signed-off-by: Paolo Abeni <pabeni@redhat.com>
Add tests to validate the neigh_forward_grat bridge option for selective
forwarding of gratuitous neighbor announcements.
The tests verify per-port and per-VLAN control of gratuitous neighbor
announcement forwarding for both IPv4 (gratuitous ARP) and IPv6
(unsolicited NA):
- When neigh_suppress is enabled with neigh_forward_grat off (default),
gratuitous announcements are suppressed
- When neigh_forward_grat is enabled, gratuitous announcements are
forwarded while regular neighbor discovery remains suppressed
For IPv4, use arping to send gratuitous ARP packets. For IPv6, use
mausezahn to craft unsolicited Neighbor Advertisement packets.
For the per-port tests, the IPv4 test exercises the ip link interface,
while the IPv6 test exercises the bridge link interface.
The per-VLAN tests use the bridge interface throughout, as per-VLAN
attributes are only accessible via 'bridge vlan'.
Signed-off-by: Danielle Ratson <danieller@nvidia.com>
Link: https://patch.msgid.link/20260511065936.4173106-7-danieller@nvidia.com
Signed-off-by: Paolo Abeni <pabeni@redhat.com>
Add netlink handlers for the per-VLAN neigh_forward_grat option via
BRIDGE_VLANDB_ENTRY_NEIGH_FORWARD_GRAT attribute.
The per-VLAN option provides fine-grained control, allowing different
VLANs on the same port to have different gratuitous ARP/unsolicited NA
forwarding behavior.
This enables control via 'bridge' commands:
# bridge vlan set dev eth0 vid 10 neigh_suppress on
# bridge vlan set dev eth0 vid 10 neigh_forward_grat on
Reviewed-by: Ido Schimmel <idosch@nvidia.com>
Reviewed-by: Petr Machata <petrm@nvidia.com>
Signed-off-by: Danielle Ratson <danieller@nvidia.com>
Acked-by: Nikolay Aleksandrov <razor@blackwall.org>
Link: https://patch.msgid.link/20260511065936.4173106-6-danieller@nvidia.com
Signed-off-by: Paolo Abeni <pabeni@redhat.com>
Add netlink handlers for the port-level neigh_forward_grat option via
IFLA_BRPORT_NEIGH_FORWARD_GRAT attribute.
The default value of OFF preserves existing behavior, i.e. gratuitous ARP
and unsolicited NA are suppressed when neigh_suppress is enabled. Users can
explicitly set it to ON to allow these packets through.
Example for enabling control via 'bridge link' command:
# bridge link set dev eth0 neigh_suppress on
# bridge link set dev eth0 neigh_forward_grat on
Reviewed-by: Ido Schimmel <idosch@nvidia.com>
Reviewed-by: Petr Machata <petrm@nvidia.com>
Signed-off-by: Danielle Ratson <danieller@nvidia.com>
Acked-by: Nikolay Aleksandrov <razor@blackwall.org>
Link: https://patch.msgid.link/20260511065936.4173106-5-danieller@nvidia.com
Signed-off-by: Paolo Abeni <pabeni@redhat.com>
The existing neighbor suppression unconditionally suppresses gratuitous
ARPs and unsolicited Neighbor Advertisements, which prevents fast
mobility of hosts between VTEPs.
Add the neigh_forward_grat option to allow selective control of gratuitous
neighbor announcements. When neigh_suppress is enabled but
neigh_forward_grat is disabled (default), gratuitous announcements are
suppressed. When neigh_forward_grat is enabled, gratuitous announcements
are forwarded while regular neighbor discovery remains suppressed.
The implementation provides per-output-port control by:
1. Adding a 'grat_arp' flag to BR_INPUT_SKB_CB to mark gratuitous ARPs and
unsolicited NAs.
2. Setting both grat_arp and proxyarp_replied flags in
br_do_proxy_suppress_arp() and br_do_suppress_nd() when gratuitous
packets are detected.
3. Checking neigh_forward_grat per output port during flooding:
- For gratuitous ARPs/NAs: suppress unless the output port has
neigh_forward_grat enabled.
- For regular ARPs/NDs: maintain existing behavior.
This allows gratuitous announcements from any input port to be selectively
forwarded based on each output port's individual neigh_forward_grat
setting, enabling gratuitous neighbor announcements to be flooded to the
VXLAN fabric.
Regular neighbor discovery (ARP requests, NS queries, solicited replies)
remains controlled by neigh_suppress and is unaffected.
Reviewed-by: Ido Schimmel <idosch@nvidia.com>
Reviewed-by: Petr Machata <petrm@nvidia.com>
Signed-off-by: Danielle Ratson <danieller@nvidia.com>
Acked-by: Nikolay Aleksandrov <razor@blackwall.org>
Link: https://patch.msgid.link/20260511065936.4173106-4-danieller@nvidia.com
Signed-off-by: Paolo Abeni <pabeni@redhat.com>
Add internal flags for the neigh_forward_grat feature:
- BR_NEIGH_FORWARD_GRAT: Port-level flag
- BR_VLFLAG_NEIGH_FORWARD_GRAT_ENABLED: Per-VLAN flag
These will be used to control whether gratuitous ARP and unsolicited NA
packets are forwarded when neighbor suppression is enabled.
Reviewed-by: Petr Machata <petrm@nvidia.com>
Reviewed-by: Ido Schimmel <idosch@nvidia.com>
Signed-off-by: Danielle Ratson <danieller@nvidia.com>
Acked-by: Nikolay Aleksandrov <razor@blackwall.org>
Link: https://patch.msgid.link/20260511065936.4173106-3-danieller@nvidia.com
Signed-off-by: Paolo Abeni <pabeni@redhat.com>
Add netlink attributes for controlling gratuitous ARP and unsolicited NA
forwarding when neighbor suppression is enabled.
Add IFLA_BRPORT_NEIGH_FORWARD_GRAT for port-level control and
BRIDGE_VLANDB_ENTRY_NEIGH_FORWARD_GRAT for per-VLAN control.
The new attributes provide independent control of gratuitous ARP and
unsolicited NA packets. Operators can enable forwarding for those packets
for fast mobility across VTEPs while keeping general neighbor suppression
active.
Reviewed-by: Ido Schimmel <idosch@nvidia.com>
Signed-off-by: Danielle Ratson <danieller@nvidia.com>
Link: https://patch.msgid.link/20260511065936.4173106-2-danieller@nvidia.com
Signed-off-by: Paolo Abeni <pabeni@redhat.com>
After switching to the real data pages, the sequence counter needs to be
reloaded from there. The code using vdso_read_begin_timens() assumed
this worked by 'continue' jumping to the *beginning* of the do-while
retry loop. However the 'continue' jumps to the *end* of said loop,
evaluating the exit condition. If the data page has a sequence counter
of '1' it will match the one from the time namespace page and prematurely
exit the retry loop. This would result in garbage returned to the caller.
Reload the sequence counter after switching the pages by using an inner
while loop again, which will loop at most once.
The loop generates slightly better code than an explicit reload through
'seq = vdso_read_begin()'.
Fixes: ed78b7b2c5 ("vdso/gettimeofday: Add a helper to read the sequence lock of a time namespace aware clock")
Reported-by: Ricardo Ribalda <ribalda@chromium.org>
Signed-off-by: Thomas Weißschuh <thomas.weissschuh@linutronix.de>
Signed-off-by: Thomas Gleixner <tglx@kernel.org>
Tested-by: Ricardo Ribalda <ribalda@chromium.org>
Reviewed-by: Christophe Leroy (CS GROUP) <chleroy@kernel.org>
Link: https://patch.msgid.link/20260422-vdso-aux-timens-loop-v1-1-e2dd8c7164cc@linutronix.de
Closes: https://lore.kernel.org/lkml/CANiDSCsOy0P1if-gJZqOM5pTJ0RDcwVfru1B7KFbTOEMqjPKJw@mail.gmail.com/
On the SMC-D client, slot 0 of ini->ism_dev[]/ini->ism_chid[] is
reserved for an SMC-Dv1 device. smc_find_ism_v2_device_clnt()
populates V2 entries starting at index 1, so when no V1 device is
selected slot 0 is left in its kzalloc()'ed state with ism_dev[0] ==
NULL and ism_chid[0] == 0.
smc_v2_determine_accepted_chid() then matches the peer's CHID against
the array starting from index 0 using the CHID alone. A malicious
peer replying to a SMC-Dv2-only proposal with d1.chid == 0 matches
the empty slot, ini->ism_selected becomes 0, and the subsequent
ism_dev[0]->lgr_lock dereference in smc_conn_create() faults at
offsetof(struct smcd_dev, lgr_lock) == 0x68:
BUG: KASAN: null-ptr-deref in _raw_spin_lock_bh+0x79/0xe0
Write of size 4 at addr 0000000000000068 by task exploit/144
Call Trace:
_raw_spin_lock_bh
smc_conn_create (net/smc/smc_core.c:1997)
__smc_connect (net/smc/af_smc.c:1447)
smc_connect (net/smc/af_smc.c:1720)
__sys_connect
__x64_sys_connect
do_syscall_64
Require ism_dev[i] to be non-NULL before accepting a CHID match.
Fixes: a7c9c5f4af ("net/smc: CLC accept / confirm V2")
Reported-by: Weiming Shi <bestswngs@gmail.com>
Assisted-by: Claude:claude-opus-4-7
Signed-off-by: Xiang Mei <xmei5@asu.edu>
Link: https://patch.msgid.link/20260511062138.2839584-1-xmei5@asu.edu
Signed-off-by: Paolo Abeni <pabeni@redhat.com>
Stephen Hemminger says:
====================
net/sched: netem: enhancements
This is a collection of improvements to netem found while
investigating the fixes now in net tree.
v5 - minor cleanups
- add allocation_errors counter
- align counters with where impairment occurs
====================
Link: https://patch.msgid.link/20260509171123.307549-1-stephen@networkplumber.org
Signed-off-by: Paolo Abeni <pabeni@redhat.com>
Add 64-bit counters for each impairment netem applies (delay, loss,
ECN marking, corruption, duplication, reordering) and for skb
allocation failures during enqueue. Exposed through TCA_STATS_APP
as struct tc_netem_xstats.
Counters increment when an impairment is occurs, independent of later
events that may mask its on-wire effect. Added allocation_errors
(similar to sch_fq) to account for when impairment could not be
applied due to memory pressure, etc.
Signed-off-by: Stephen Hemminger <stephen@networkplumber.org>
Link: https://patch.msgid.link/20260509171123.307549-6-stephen@networkplumber.org
Signed-off-by: Paolo Abeni <pabeni@redhat.com>
The packet corruption code only flipped bits in the linear
header portion of the skb, skipping corruption when
skb_headlen() was zero.
Linearize the whole skb if necessary before corruption.
Extends d64cb81dcb ("net/sched: sch_netem: fix out-of-bounds access
in packet corruption") with a more general solution.
Signed-off-by: Stephen Hemminger <stephen@networkplumber.org>
Link: https://patch.msgid.link/20260509171123.307549-5-stephen@networkplumber.org
Signed-off-by: Paolo Abeni <pabeni@redhat.com>
Use netlink extack to report errors instead of sending them
to the kernel log with pr_info(). The error message can them be seen
with tc commands; and avoids log spam.
Signed-off-by: Stephen Hemminger <stephen@networkplumber.org>
Link: https://patch.msgid.link/20260509171123.307549-4-stephen@networkplumber.org
Signed-off-by: Paolo Abeni <pabeni@redhat.com>
The current layout of struct netem_sched_data can be improved
by optimizing cache locality, compacting data types (use u8
for enum) and eliminating unused elements.
Reorganize the struct as follows:
- Cacheline 0 holds the tfifo state (t_root/t_head/t_tail/t_len),
counter, and the unconditional enqueue scalars
latency/jitter/rate/gap/loss.
- Cacheline 1 holds the remaining zero-check scalars
(duplicate/reorder/corrupt/ecn), all five crndstate correlation
structures, and loss_model.
- Cacheline 2 holds prng, delay_dist, the slot dequeue state,
slot_dist, and the inner classful qdisc pointer.
- Rate-shaping fields, q->limit (config-only; the fast path reads
sch->limit), and the CLG Markov state move to the warm tail.
- tc_netem_slot slot_config and qdisc_watchdog (only consulted on
slot reschedule and watchdog wake) move to the cold tail.
Also reorder struct clgstate to place the u8 state member after the
u32 transition probabilities. This removes the 3-byte interior hole
without changing the struct's size.
Should have no functional change.
Signed-off-by: Stephen Hemminger <stephen@networkplumber.org>
Link: https://patch.msgid.link/20260509171123.307549-2-stephen@networkplumber.org
Signed-off-by: Paolo Abeni <pabeni@redhat.com>
__destroy_component_cfg() is called to free the configuration array.
It uses the embedded 'garbage' structure, which means the array has
to be allocated.
If __destroy_component_cfg() is called from mpam_disable() before the
configuration was ever allocated, then a NULL pointer is dereferenced.
Check for this case and return early if the configuration is not
allocated.
__destroy_component_cfg() also frees the mbwu_state as this is allocated
by __allocate_component_cfg(). As the mbwu_state is allocated after
comp->cfg is set, and is also under mpam_list_lock, only the first
pointer needs checking.
Fixes: 3bd04fe7d8 ("arm_mpam: Extend reset logic to allow devices to be reset any time")
Cc: <stable@vger.kernel.org>
Signed-off-by: James Morse <james.morse@arm.com>
Reviewed-by: Ben Horgan <ben.horgan@arm.com>
Signed-off-by: Catalin Marinas <catalin.marinas@arm.com>
mpam_assert_partid_sizes_fixed() is used to document that the caller
doesn't expect the discovered PARTID size to change while it is walking
a list sized by PARTID. Typically the MSC state is not written to until
all the MSC have been discovered and this value is set.
However, if discovering the MSC fails and schedules mpam_disable(),
then the MSC state is written to reset it. In this case the
discovered PARTID size may be become smaller - but only PARTID 0
will be used once resctrl_exit() has been called.
Skip the WARN_ON_ONCE() if mpam_disable_reason has been set.
Fixes: 3bd04fe7d8 ("arm_mpam: Extend reset logic to allow devices to be reset any time")
Cc: <stable@vger.kernel.org>
Signed-off-by: James Morse <james.morse@arm.com>
Reviewed-by: Ben Horgan <ben.horgan@arm.com>
Signed-off-by: Catalin Marinas <catalin.marinas@arm.com>
mpam_ris_hw_probe_csu_nrdy() sets and clears MSMON_CSU.NRDY and checks
whether it's configuration sticks. However, hardware isn't given a chance
to disagree. Based on rule LRTGP, in MPAM specification IHI0099 version
B.b, the hardware will set NRDY if it needs time to establish a count after
a configuration change.
Enable the monitor so that NRDY becomes relevant and change the
configuration after clearing NRDY to try and coax the hardware into setting
it.
Fixes: 8c90dc68a5 ("arm_mpam: Probe the hardware features resctrl supports")
Cc: <stable@vger.kernel.org>
Signed-off-by: Ben Horgan <ben.horgan@arm.com>
Reviewed-by: James Morse <james.morse@arm.com>
Signed-off-by: Catalin Marinas <catalin.marinas@arm.com>
Rule ZTXDS of the MPAM specification, IHI009 version B.b, states: "If a
monitor does not support automatic updates of NRDY, software can use that
bit for any purpose."
As software is not reliably informed whether or not the monitor supports
automatic updates of NRDY always assume that hardware may manage NRDY but
don't rely on it. When NRDY is truly untouched by hardware then, as it is
written to 0 on configuration, it will always read 0.
At probe it's checked if MSMON_CSU.NRDY and MSMON_MBWU.NRDY are hardware
managed but not MSMON_MBWU_L.NDRY. Specialize the checking for hardware
managed NRDY to CSU counters as this is the only case where hardware
management makes sense. Continue to inform the user if MSMON_CSU.NRDY
appears to be hardware managed but the firmware doesn't provide the
associated time limit for the automatic clearing of NRDY. Remove the NRDY
feature flags as they are now unused.
Fixes: 8c90dc68a5 ("arm_mpam: Probe the hardware features resctrl supports")
Cc: <stable@vger.kernel.org>
Signed-off-by: Ben Horgan <ben.horgan@arm.com>
Reviewed-by: James Morse <james.morse@arm.com>
Signed-off-by: Catalin Marinas <catalin.marinas@arm.com>
In _mpam_ris_hw_probe_hw_nrdy() a new register value to select the first
monitor and relevant RIS is prepared in mon_sel. However, it is written to
the monitor value register, e.g. MSMON_CSU, rather than MSMON_CFG_MON_SEL.
As MSMON_CFG_MON_SEL is a 32 bit register update the type of mon_sel to
u32. Write mon_sel to the intended register, MSMON_CFG_MON_SEL.
Fixes: 8c90dc68a5 ("arm_mpam: Probe the hardware features resctrl supports")
Cc: <stable@vger.kernel.org>
Signed-off-by: Ben Horgan <ben.horgan@arm.com>
Reviewed-by: James Morse <james.morse@arm.com>
Signed-off-by: Catalin Marinas <catalin.marinas@arm.com>
The mm-api kernel-docs have been disconnected from their symbols. While
the scripts were previously taught to handle the _noprof suffix added by
allocation tagging (in 51a7bf0238 "scripts/kernel-doc: drop "_noprof"
on function prototypes"), this does not handle cases where the internal
implementation function has an additional leading underscore. The added
optional parameters (via DECL_KMALLOC_PARAMS) further complicate parsing
the internal signatures.
When the kernel-doc block remains above the internal implementation
function but uses the public API name, the documentation generator fails
to associate the documented symbol.
Simply moving the docs to the macros in slab.h fixes the association but
causes loss of types in the generated documentation (rendering as e.g.
untyped 'kmalloc(size, flags)' macro).
Fix this by:
1. Moving the kernel-doc comment blocks from slub.c to slab.h, placing
them directly above the user-facing macros.
2. Providing explicit, typed C prototypes for the documented APIs inside
'#if 0 /* kernel-doc */' blocks.
3. Converting the variadic macros for the documented APIs to use
explicit arguments to match the documentation.
No functional change intended.
Signed-off-by: Marco Elver <elver@google.com>
Link: https://patch.msgid.link/20260511200136.3201646-3-elver@google.com
Signed-off-by: Vlastimil Babka (SUSE) <vbabka@kernel.org>
When using CONFIG_KMALLOC_PARTITION_RANDOM, _RET_IP_ was previously used
to identify the allocation site. _RET_IP_, however, evaluates to the
caller's parent's instruction pointer rather than the actual allocation
site; this would lead to collisions where a function performs multiple
allocations.
With the generalization to kmalloc_token_t, we now generate the token at
the outermost macro, and using _THIS_IP_ would fix this for all cases.
Unfortunately, the generic implementation of _THIS_IP_ relies on taking
the address of a local label, which is considered broken by both GCC [1]
and Clang [2] because label addresses are only expected to be used with
computed gotos. While the generic version more or less works today, it
is known to be brittle. For example, Clang -O2 always returns 1 when
this function is inlined:
static inline unsigned long get_ip(void)
{ return ({ __label__ __here; __here: (unsigned long)&&__here; }); }
To provide a reliable unique identifier without breaking architectures
relying on the generic _THIS_IP_, introduce _CODE_LOCATION_: it resolves
to _THIS_IP_ where architectures provide a safe implementation, and
falls back to a zero-cost static marker where _THIS_IP_ is broken.
Link: https://gcc.gnu.org/bugzilla/show_bug.cgi?id=120071 [1]
Link: https://github.com/llvm/llvm-project/issues/138272 [2]
Signed-off-by: Marco Elver <elver@google.com>
Reviewed-by: Harry Yoo (Oracle) <harry@kernel.org>
Link: https://patch.msgid.link/20260511200136.3201646-2-elver@google.com
Signed-off-by: Vlastimil Babka (SUSE) <vbabka@kernel.org>
Rework the general infrastructure around RANDOM_KMALLOC_CACHES into more
flexible KMALLOC_PARTITION_CACHES, with the former being a partitioning
mode of the latter.
Introduce a new mode, KMALLOC_PARTITION_TYPED, which leverages a feature
available in Clang 22 and later, called "allocation tokens" via
__builtin_infer_alloc_token() [1]. Unlike KMALLOC_PARTITION_RANDOM
(formerly RANDOM_KMALLOC_CACHES), this mode deterministically assigns a
slab cache to an allocation of type T, regardless of allocation site.
The builtin __builtin_infer_alloc_token(<malloc-args>, ...) instructs
the compiler to infer an allocation type from arguments commonly passed
to memory-allocating functions and returns a type-derived token ID. The
implementation passes kmalloc-args to the builtin: the compiler performs
best-effort type inference, and then recognizes common patterns such as
`kmalloc(sizeof(T), ...)`, `kmalloc(sizeof(T) * n, ...)`, but also
`(T *)kmalloc(...)`. Where the compiler fails to infer a type the
fallback token (default: 0) is chosen.
Note: kmalloc_obj(..) APIs fix the pattern how size and result type are
expressed, and therefore ensures there's not much drift in which
patterns the compiler needs to recognize. Specifically, kmalloc_obj()
and friends expand to `(TYPE *)KMALLOC(__obj_size, GFP)`, which the
compiler recognizes via the cast to TYPE*.
Clang's default token ID calculation is described as [1]:
typehashpointersplit: This mode assigns a token ID based on the hash
of the allocated type's name, where the top half ID-space is reserved
for types that contain pointers and the bottom half for types that do
not contain pointers.
Separating pointer-containing objects from pointerless objects and data
allocations can help mitigate certain classes of memory corruption
exploits [2]: attackers who gains a buffer overflow on a primitive
buffer cannot use it to directly corrupt pointers or other critical
metadata in an object residing in a different, isolated heap region.
It is important to note that heap isolation strategies offer a
best-effort approach, and do not provide a 100% security guarantee,
albeit achievable at relatively low performance cost. Note that this
also does not prevent cross-cache attacks: while waiting for future
features like SLAB_VIRTUAL [3] to provide physical page isolation, this
feature should be deployed alongside SHUFFLE_PAGE_ALLOCATOR and
init_on_free=1 to mitigate cross-cache attacks and page-reuse attacks as
much as possible today.
With all that, my kernel (x86 defconfig) shows me a histogram of slab
cache object distribution per /proc/slabinfo (after boot):
<slab cache> <objs> <hist>
kmalloc-part-15 1465 ++++++++++++++
kmalloc-part-14 2988 +++++++++++++++++++++++++++++
kmalloc-part-13 1656 ++++++++++++++++
kmalloc-part-12 1045 ++++++++++
kmalloc-part-11 1697 ++++++++++++++++
kmalloc-part-10 1489 ++++++++++++++
kmalloc-part-09 965 +++++++++
kmalloc-part-08 710 +++++++
kmalloc-part-07 100 +
kmalloc-part-06 217 ++
kmalloc-part-05 105 +
kmalloc-part-04 4047 ++++++++++++++++++++++++++++++++++++++++
kmalloc-part-03 183 +
kmalloc-part-02 283 ++
kmalloc-part-01 316 +++
kmalloc 1422 ++++++++++++++
The above /proc/slabinfo snapshot shows me there are 6673 allocated
objects (slabs 00 - 07) that the compiler claims contain no pointers or
it was unable to infer the type of, and 12015 objects that contain
pointers (slabs 08 - 15). On a whole, this looks relatively sane.
Additionally, when I compile my kernel with -Rpass=alloc-token, which
provides diagnostics where (after dead-code elimination) type inference
failed, I see 186 allocation sites where the compiler failed to identify
a type (down from 966 when I sent the RFC [4]). Some initial review
confirms these are mostly variable sized buffers, but also include
structs with trailing flexible length arrays.
Link: https://clang.llvm.org/docs/AllocToken.html [1]
Link: https://blog.dfsec.com/ios/2025/05/30/blasting-past-ios-18/ [2]
Link: https://lwn.net/Articles/944647/ [3]
Link: https://lore.kernel.org/all/20250825154505.1558444-1-elver@google.com/ [4]
Link: https://discourse.llvm.org/t/rfc-a-framework-for-allocator-partitioning-hints/87434
Acked-by: GONG Ruiqi <gongruiqi1@huawei.com>
Co-developed-by: Harry Yoo (Oracle) <harry@kernel.org>
Signed-off-by: Harry Yoo (Oracle) <harry@kernel.org>
Signed-off-by: Marco Elver <elver@google.com>
Reviewed-by: Harry Yoo (Oracle) <harry@kernel.org>
Link: https://patch.msgid.link/20260511200136.3201646-1-elver@google.com
Signed-off-by: Vlastimil Babka (SUSE) <vbabka@kernel.org>
tfcpad is a u32, but that full range is excessive for padding.
Limit it to max IP length (64k).
Signed-off-by: David Ahern <dahern@nvidia.com>
Signed-off-by: Steffen Klassert <steffen.klassert@secunet.com>
Leo Lin reported OOB write issue in esp component:
xfrm_state_mtu() returns u32 but performs its arithmetic in unsigned
modulo-2^32 space using an attacker-influenced "header_len + authsize +
net_adj" subtracted from a small "mtu" argument. A nobody user can
install an IPv4 ESP tunnel SA with a large authentication key
(XFRMA_ALG_AUTH_TRUNC, e.g. hmac(sha512), 64-byte key, 64-byte trunc),
configure a small interface MTU (68 bytes), and set XFRMA_TFCPAD to a
large value. When a single UDP datagram is then sent through the
tunnel, xfrm_state_mtu() underflows to a near-2^32 value, and
esp_output() consumes it as a signed int via:
padto = min(x->tfcpad, xfrm_state_mtu(x, mtu_cached))
esp.tfclen = padto - skb->len (assigned to int)
esp.tfclen ends up negative (e.g. -207). It is sign-extended to size_t
when passed to memset() inside esp_output_fill_trailer(), producing a
~16 EB write of zeroes at skb_tail_pointer(skb). KASAN logs it as
"Write of size 18446744073709551537 at addr ffff888...".
Check for underflow and return 1. This causes the sendmsg attempt to
fail with ENETUNREACH.
Fixes: c5c2523893 ("[XFRM]: Optimize MTU calculation")
Reported-by: Leo Lin <leo@depthfirst.com>
Assisted-by: Codex:26.506.31004
Signed-off-by: David Ahern <dahern@nvidia.com>
Signed-off-by: Steffen Klassert <steffen.klassert@secunet.com>
Allocations from a fresh slab can consume all of its objects, and the
freelist built during slab allocation is discarded immediately as a result.
Instead of special-casing the whole-slab bulk refill case, defer freelist
construction until after objects are emitted from a fresh slab.
new_slab() now only allocates the slab and initializes its metadata.
refill_objects() then obtains a fresh slab and lets alloc_from_new_slab()
emit objects directly, building a freelist only for the objects left
unallocated; the same change is applied to alloc_single_from_new_slab().
To keep CONFIG_SLAB_FREELIST_RANDOM=y/n on the same path, introduce a
small iterator abstraction for walking free objects in allocation order.
The iterator is used both for filling the sheaf and for building the
freelist of the remaining objects.
Also mark setup_object() inline. After this optimization, the compiler no
longer consistently inlines this helper in the hot path, which can hurt
performance. Explicitly marking it inline restores the expected code
generation.
This reduces per-object overhead when allocating from a fresh slab.
The most direct benefit is in the paths that allocate objects first and
only build a freelist for the remainder afterward: bulk allocation from
a new slab in refill_objects(), single-object allocation from a new slab
in ___slab_alloc(), and the corresponding early-boot paths that now use
the same deferred-freelist scheme. Since refill_objects() is also used to
refill sheaves, the optimization is not limited to the small set of
kmem_cache_alloc_bulk()/kmem_cache_free_bulk() users; regular allocation
workloads may benefit as well when they refill from a fresh slab.
In slub_bulk_bench, the time per object drops by about 42% to 70% with
CONFIG_SLAB_FREELIST_RANDOM=n, and by about 58% to 69% with
CONFIG_SLAB_FREELIST_RANDOM=y. This benchmark is intended to isolate the
cost removed by this change: each iteration allocates exactly
slab->objects from a fresh slab. That makes it a near best-case scenario
for deferred freelist construction, because the old path still built a
full freelist even when no objects remained, while the new path avoids
that work. Realistic workloads may see smaller end-to-end gains depending
on how often allocations reach this fresh-slab refill path.
Benchmark results (slub_bulk_bench):
Machine: qemu-system-x86 -m 1024M -smp 8 -enable-kvm -cpu host
Kernel: Linux 7.1.0-rc1-next-20260429
Config: x86_64_defconfig
Cpu: 0
Rounds: 20
Total: 256MB
- CONFIG_SLAB_FREELIST_RANDOM=n -
obj_size=16, batch=256:
before: 5.44 +- 0.07 ns/object
after: 3.12 +- 0.03 ns/object
delta: -42.6%
obj_size=32, batch=128:
before: 7.57 +- 0.32 ns/object
after: 3.79 +- 0.07 ns/object
delta: -49.9%
obj_size=64, batch=64:
before: 11.27 +- 0.09 ns/object
after: 4.83 +- 0.06 ns/object
delta: -57.2%
obj_size=128, batch=32:
before: 19.38 +- 0.13 ns/object
after: 6.43 +- 0.08 ns/object
delta: -66.8%
obj_size=256, batch=32:
before: 23.59 +- 0.18 ns/object
after: 6.97 +- 0.07 ns/object
delta: -70.5%
obj_size=512, batch=32:
before: 21.06 +- 0.14 ns/object
after: 7.12 +- 0.17 ns/object
delta: -66.2%
- CONFIG_SLAB_FREELIST_RANDOM=y -
obj_size=16, batch=256:
before: 9.42 +- 0.11 ns/object
after: 4.36 +- 0.19 ns/object
delta: -53.7%
obj_size=32, batch=128:
before: 12.19 +- 0.62 ns/object
after: 4.93 +- 0.07 ns/object
delta: -59.6%
obj_size=64, batch=64:
before: 17.01 +- 0.73 ns/object
after: 6.14 +- 0.12 ns/object
delta: -63.9%
obj_size=128, batch=32:
before: 23.71 +- 1.10 ns/object
after: 8.35 +- 0.18 ns/object
delta: -64.8%
obj_size=256, batch=32:
before: 29.20 +- 0.35 ns/object
after: 9.44 +- 1.32 ns/object
delta: -67.7%
obj_size=512, batch=32:
before: 29.35 +- 0.79 ns/object
after: 9.21 +- 0.34 ns/object
delta: -68.6%
Link: https://github.com/HSM6236/slub_bulk_test.git
Suggested-by: Harry Yoo (Oracle) <harry@kernel.org>
Reviewed-by: Harry Yoo (Oracle) <harry@kernel.org>
Reviewed-by: Hao Li <hao.li@linux.dev>
Tested-by: Hao Li <hao.li@linux.dev>
Signed-off-by: Shengming Hu <hu.shengming@zte.com.cn>
Link: https://patch.msgid.link/202604302204413066CxdJnJ3RAGH_7iE4EBIO@zte.com.cn
Signed-off-by: Vlastimil Babka (SUSE) <vbabka@kernel.org>
A kernel panic is observed when handling machine check exceptions from
real mode.
BUG: Unable to handle kernel data access on read at 0xc00000006be21300
Oops: Kernel access of bad area, sig: 11 [#1]
MSR: 8000000000001003 <SF,ME,RI,LE> CR: 88222248 XER: 00000005
CFAR: c00000000003ffc4 DAR: c00000006be21300 DSISR: 40000000 IRQMASK: 0
NIP [c000000000029e40] arch_irq_work_raise+0x10/0x70
LR [c00000000003ffc8] machine_check_queue_event+0xa8/0x150
Call Trace:
[c0000000179d3c70] [c00000000003ff64] machine_check_queue_event+0x44/0x150
[c0000000179d3d30] [c0000000000084e0] machine_check_early_common+0x1f0/0x2c0
The crash occurs because arch_irq_work_raise() calls preempt_disable()
from machine check exception (MCE) handlers running in real mode. In
this context, accessing the preempt_count can fault, leading to the panic.
The preempt_disable()/preempt_enable() pair in arch_irq_work_raise()
was originally added by commit 0fe1ac48be ("powerpc/perf_event: Fix
oops due to perf_event_do_pending call") to avoid races while raising
irq work from exception context.
Later, commit 471ba0e686 ("irq_work: Do not raise an IPI when
queueing work on the local CPU") added preemption protection in
irq_work_queue() path, while commit 20b876918c ("irq_work: Use per
cpu atomics instead of regular atomics") added equivalent
protection in irq_work_queue_on() before reaching arch_irq_work_raise():
irq_work_queue() / irq_work_queue_on()
-> preempt_disable()
-> __irq_work_queue_local()
-> irq_work_raise()
-> arch_irq_work_raise()
As a result, callers other than mce_irq_work_raise() already execute
with preemption disabled, making the additional
preempt_disable()/preempt_enable() pair in arch_irq_work_raise()
redundant.
The arch_irq_work_raise() function executes in NMI context when called
from MCE handler. Hence we will not be preempted or scheduled out since
we are in NMI context with MSR[EE]=0. Therefore, it is safe to remove
the preempt_disable()/preempt_enable() calls from here.
Remove it to avoid accessing preempt_count from real mode context.
Fixes: cc15ff3275 ("powerpc/mce: Avoid using irq_work_queue() in realmode")
Suggested-by: Mahesh Salgaonkar <mahesh@linux.ibm.com>
Acked-by: Shrikanth Hegde <sshegde@linux.ibm.com>
Reviewed-by: Ritesh Harjani (IBM) <ritesh.list@gmail.com>
Signed-off-by: Sayali Patil <sayalip@linux.ibm.com>
[Maddy: Fixed the commit title]
Signed-off-by: Madhavan Srinivasan <maddy@linux.ibm.com>
Link: https://patch.msgid.link/20260513081413.222490-1-sayalip@linux.ibm.com
The Lenovo ThinkPad E490 (PNP ID: LEN2058) has a Synaptics TM3471-020
touchpad that supports SMBus/RMI4 mode but is not listed in
smbus_pnp_ids[]. Without this entry, RMI4 over SMBus is not enabled
by default, and the touchpad falls back to PS/2 mode.
Adding LEN2058 to the passlist enables automatic RMI4 detection without
requiring the psmouse.synaptics_intertouch parameter, and matches
the behavior of similar ThinkPad models already in the list
(E480/LEN2054, E580/LEN2055).
Tested on ThinkPad E490 with kernel 7.0.5-zen1 and Arch Linux.
RMI4 over SMBus is confirmed working without any kernel parameters.
Signed-off-by: Nicolás Bazaes <contacto@bazaes.cl>
Assisted-by: Claude:claude-sonnet-4-6
Link: https://patch.msgid.link/20260514013552.14234-1-contacto@bazaes.cl
Cc: stable@vger.kernel.org
Signed-off-by: Dmitry Torokhov <dmitry.torokhov@gmail.com>
The unaligned access emulation code in Linux has various deficiencies.
For example, it doesn't emulate vector instructions [1] [2], and doesn't
emulate KVM guest accesses. Therefore, requesting misaligned exception
delegation with SBI FWFT actually regresses vector instructions' and KVM
guests' behavior.
Until Linux can handle it properly, guard these sbi_fwft_set() calls
behind RISCV_SBI_FWFT_DELEGATE_MISALIGNED, which in turn depends on
NONPORTABLE. Those who are sure that this wouldn't be a problem can
enable this option, perhaps getting better performance.
The rest of the existing code proceeds as before, except as if
SBI_FWFT_MISALIGNED_EXC_DELEG is not available, to handle any remaining
address misaligned exceptions on a best-effort basis. The KVM SBI FWFT
implementation is also not touched, but it is disabled if the firmware
emulates unaligned accesses.
Cc: stable@vger.kernel.org
Fixes: cf5a8abc65 ("riscv: misaligned: request misaligned exception from SBI")
Reported-by: Songsong Zhang <U2FsdGVkX1@gmail.com> # KVM
Link: https://lore.kernel.org/linux-riscv/38ce44c1-08cf-4e3f-8ade-20da224f529c@iscas.ac.cn/ [1]
Link: https://lore.kernel.org/linux-riscv/b3cfcdac-0337-4db0-a611-258f2868855f@iscas.ac.cn/ [2]
Signed-off-by: Vivian Wang <wangruikang@iscas.ac.cn>
Acked-by: Conor Dooley <conor.dooley@microchip.com>
Link: https://patch.msgid.link/20260401-riscv-misaligned-dont-delegate-v2-1-5014a288c097@iscas.ac.cn
Signed-off-by: Paul Walmsley <pjw@kernel.org>
