x86/boot/sev: Avoid shared GHCB page for early memory acceptance
Communicating with the hypervisor using the shared GHCB page requires
clearing the C bit in the mapping of that page. When executing in the
context of the EFI boot services, the page tables are owned by the
firmware, and this manipulation is not possible.
So switch to a different API for accepting memory in SEV-SNP guests, one
which is actually supported at the point during boot where the EFI stub
may need to accept memory, but the SEV-SNP init code has not executed
yet.
For simplicity, also switch the memory acceptance carried out by the
decompressor when not booting via EFI - this only involves the
allocation for the decompressed kernel, and is generally only called
after kexec, as normal boot will jump straight into the kernel from the
EFI stub.
Sandipan Das [Fri, 18 Apr 2025 06:19:40 +0000 (11:49 +0530)]
x86/cpu/amd: Fix workaround for erratum 1054
Erratum 1054 affects AMD Zen processors that are a part of Family 17h
Models 00-2Fh and the workaround is to not set HWCR[IRPerfEn]. However,
when X86_FEATURE_ZEN1 was introduced, the condition to detect unaffected
processors was incorrectly changed in a way that the IRPerfEn bit gets
set only for unaffected Zen 1 processors.
Ensure that HWCR[IRPerfEn] is set for all unaffected processors. This
includes a subset of Zen 1 (Family 17h Models 30h and above) and all
later processors. Also clear X86_FEATURE_IRPERF on affected processors
so that the IRPerfCount register is not used by other entities like the
MSR PMU driver.
Pi Xiange [Mon, 14 Apr 2025 03:28:39 +0000 (11:28 +0800)]
x86/cpu: Add CPU model number for Bartlett Lake CPUs with Raptor Cove cores
Bartlett Lake has a P-core only product with Raptor Cove.
[ mingo: Switch around the define as pointed out by Christian Ludloff:
Ratpr Cove is the core, Bartlett Lake is the product.
Signed-off-by: Pi Xiange <xiange.pi@intel.com> Signed-off-by: Ingo Molnar <mingo@kernel.org> Cc: Christian Ludloff <ludloff@gmail.com> Cc: Peter Zijlstra <peterz@infradead.org> Cc: Tony Luck <tony.luck@intel.com> Cc: Andrew Cooper <andrew.cooper3@citrix.com> Cc: "H. Peter Anvin" <hpa@zytor.com> Cc: John Ogness <john.ogness@linutronix.de> Cc: "Ahmed S. Darwish" <darwi@linutronix.de> Cc: x86-cpuid@lists.linux.dev Link: https://lore.kernel.org/r/20250414032839.5368-1-xiange.pi@intel.com
x86/microcode/AMD: Extend the SHA check to Zen5, block loading of any unreleased standalone Zen5 microcode patches
All Zen5 machines out there should get BIOS updates which update to the
correct microcode patches addressing the microcode signature issue.
However, silly people carve out random microcode blobs from BIOS
packages and think are doing other people a service this way...
Block loading of any unreleased standalone Zen5 microcode patches.
Signed-off-by: Borislav Petkov (AMD) <bp@alien8.de> Signed-off-by: Ingo Molnar <mingo@kernel.org> Cc: <stable@kernel.org> Cc: Andrew Cooper <andrew.cooper3@citrix.com> Cc: Boris Ostrovsky <boris.ostrovsky@oracle.com> Cc: Linus Torvalds <torvalds@linux-foundation.org> Cc: Maciej S. Szmigiero <mail@maciej.szmigiero.name> Cc: Nikolay Borisov <nik.borisov@suse.com> Cc: Tom Lendacky <thomas.lendacky@amd.com> Link: https://lore.kernel.org/r/20250410114222.32523-1-bp@kernel.org
Jason Andryuk [Thu, 10 Apr 2025 19:31:05 +0000 (15:31 -0400)]
x86/xen: Fix __xen_hypercall_setfunc()
Hypercall detection is failing with xen_hypercall_intel() chosen even on
an AMD processor. Looking at the disassembly, the call to
xen_get_vendor() was removed.
The check for boot_cpu_has(X86_FEATURE_CPUID) was used as a proxy for
the x86_vendor having been set.
When CONFIG_X86_REQUIRED_FEATURE_CPUID=y (the default value), DCE eliminates
the call to xen_get_vendor(). An uninitialized value 0 means
X86_VENDOR_INTEL, so the Intel function is always returned.
Remove the if and always call xen_get_vendor() to avoid this issue.
Fixes: 3d37d9396eb3 ("x86/cpufeatures: Add {REQUIRED,DISABLED} feature configs") Suggested-by: Juergen Gross <jgross@suse.com> Signed-off-by: Jason Andryuk <jason.andryuk@amd.com> Signed-off-by: Ingo Molnar <mingo@kernel.org> Reviewed-by: Juergen Gross <jgross@suse.com> Cc: Boris Ostrovsky <boris.ostrovsky@oracle.com> Cc: "H. Peter Anvin" <hpa@zytor.com> Cc: "Xin Li (Intel)" <xin@zytor.com> Link: https://lore.kernel.org/r/20250410193106.16353-1-jason.andryuk@amd.com
Merge tag 'irq-urgent-2025-04-10' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip
Pull misc irqchip fixes from Ingo Molnar:
- Fix NULL pointer dereference crashes due to missing .chip_flags setup
in the sg2042-msi and irq-bcm2712-mip irqchip drivers
- Remove the davinci aintc irqchip driver's leftover header too
* tag 'irq-urgent-2025-04-10' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip:
irqchip/irq-bcm2712-mip: Set EOI/ACK flags in msi_parent_ops
irqchip/sg2042-msi: Add missing chip flags
irqchip/davinci: Remove leftover header
Merge tag 'timers-urgent-2025-04-10' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip
Pull misc timer fixes from Ingo Molnar:
- Fix missing ACCESS_PRIVATE() that triggered a Sparse warning
- Fix lockdep false positive in tick_freeze() on CONFIG_PREEMPT_RT=y
- Avoid <vdso/unaligned.h> macro's variable shadowing to address build
warning that triggers under W=2 builds
* tag 'timers-urgent-2025-04-10' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip:
vdso: Address variable shadowing in macros
timekeeping: Add a lockdep override in tick_freeze()
hrtimer: Add missing ACCESS_PRIVATE() for hrtimer::function
Merge tag 'x86-urgent-2025-04-10' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip
Pull misc x86 fixes from Ingo Molnar:
- Fix CPU topology related regression that limited Xen PV guests to a
single CPU
- Fix ancient e820__register_nosave_regions() bugs that were causing
problems with kexec's artificial memory maps
- Fix an S4 hibernation crash caused by two missing ENDBR's that were
mistakenly removed in a recent commit
- Fix a resctrl serialization bug
- Fix early_printk documentation and comments
- Fix RSB bugs, combined with preparatory updates to better match the
code to vendor recommendations.
- Add RSB mitigation document
- Fix/update documentation
- Fix the erratum_1386_microcode[] table to be NULL terminated
* tag 'x86-urgent-2025-04-10' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip:
x86/ibt: Fix hibernate
x86/cpu: Avoid running off the end of an AMD erratum table
Documentation/x86: Zap the subsection letters
Documentation/x86: Update the naming of CPU features for /proc/cpuinfo
x86/bugs: Add RSB mitigation document
x86/bugs: Don't fill RSB on context switch with eIBRS
x86/bugs: Don't fill RSB on VMEXIT with eIBRS+retpoline
x86/bugs: Fix RSB clearing in indirect_branch_prediction_barrier()
x86/bugs: Use SBPB in write_ibpb() if applicable
x86/bugs: Rename entry_ibpb() to write_ibpb()
x86/early_printk: Use 'mmio32' for consistency, fix comments
x86/resctrl: Fix rdtgroup_mkdir()'s unlocked use of kernfs_node::name
x86/e820: Fix handling of subpage regions when calculating nosave ranges in e820__register_nosave_regions()
x86/acpi: Don't limit CPUs to 1 for Xen PV guests due to disabled ACPI
Merge tag 'perf-urgent-2025-04-10' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip
Pull misc perf events fixes from Ingo Molnar:
- Fix __free_event() corner case splat
- Fix false-positive uprobes related lockdep splat on
CONFIG_PREEMPT_RT=y kernels
- Fix a complicated perf sigtrap race that may result in hangs
* tag 'perf-urgent-2025-04-10' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip:
perf: Fix hang while freeing sigtrap event
uprobes: Avoid false-positive lockdep splat on CONFIG_PREEMPT_RT=y in the ri_timer() uprobe timer callback, use raw_write_seqcount_*()
perf/core: Fix WARN_ON(!ctx) in __free_event() for partial init
* tag 'net-6.15-rc2' of git://git.kernel.org/pub/scm/linux/kernel/git/netdev/net: (38 commits)
ethtool: cmis_cdb: Fix incorrect read / write length extension
selftests: netfilter: add test case for recent mismatch bug
nft_set_pipapo: fix incorrect avx2 match of 5th field octet
net: ppp: Add bound checking for skb data on ppp_sync_txmung
net: Fix null-ptr-deref by sock_lock_init_class_and_name() and rmmod.
ipv6: Align behavior across nexthops during path selection
net: phy: allow MDIO bus PM ops to start/stop state machine for phylink-controlled PHY
net: phy: move phy_link_change() prior to mdio_bus_phy_may_suspend()
selftests/tc-testing: sfq: check that a derived limit of 1 is rejected
net_sched: sch_sfq: move the limit validation
net_sched: sch_sfq: use a temporary work area for validating configuration
net: libwx: handle page_pool_dev_alloc_pages error
selftests: mptcp: validate MPJoin HMacFailure counters
mptcp: only inc MPJoinAckHMacFailure for HMAC failures
rtnetlink: Fix bad unlock balance in do_setlink().
net: ethtool: Don't call .cleanup_data when prepare_data fails
tc: Ensure we have enough buffer space when sending filter netlink notifications
net: libwx: Fix the wrong Rx descriptor field
octeontx2-pf: qos: fix VF root node parent queue index
selftests: tls: check that disconnect does nothing
...
Merge tag 'for-linus-6.15a-rc2-tag' of git://git.kernel.org/pub/scm/linux/kernel/git/xen/tip
Pull xen fixes from Juergen Gross:
- A simple fix adding the module description of the Xenbus frontend
module
- A fix correcting the xen-acpi-processor Kconfig dependency for PVH
Dom0 support
- A fix for the Xen balloon driver when running as Xen Dom0 in PVH mode
- A fix for PVH Dom0 in order to avoid problems with CPU idle and
frequency drivers conflicting with Xen
* tag 'for-linus-6.15a-rc2-tag' of git://git.kernel.org/pub/scm/linux/kernel/git/xen/tip:
x86/xen: disable CPU idle and frequency drivers for PVH dom0
x86/xen: fix balloon target initialization for PVH dom0
xen: Change xen-acpi-processor dom0 dependency
xenbus: add module description
Merge tag 'block-6.15-20250410' of git://git.kernel.dk/linux
Pull block fixes from Jens Axboe:
- Add a missing ublk selftest script, from test additions added last
week
- Two fixes for ublk error recovery and reissue
- Cleanup of ublk argument passing
* tag 'block-6.15-20250410' of git://git.kernel.dk/linux:
ublk: pass ublksrv_ctrl_cmd * instead of io_uring_cmd *
ublk: don't fail request for recovery & reissue in case of ubq->canceling
ublk: fix handling recovery & reissue in ublk_abort_queue()
selftests: ublk: fix test_stripe_04
Merge tag 'io_uring-6.15-20250410' of git://git.kernel.dk/linux
Pull io_uring fixes from Jens Axboe:
- Reject zero sized legacy provided buffers upfront. No ill side
effects from this one, only really done to shut up a silly syzbot
test case.
- Fix for a regression in tag posting for registered files or buffers,
where the tag would be posted even when the registration failed.
- two minor zcrx cleanups for code added this merge window.
* tag 'io_uring-6.15-20250410' of git://git.kernel.dk/linux:
io_uring/kbuf: reject zero sized provided buffers
io_uring/zcrx: separate niov number from pages
io_uring/zcrx: put refill data into separate cache line
io_uring: don't post tag CQEs on file/buffer registration failure
Merge tag 'gpio-fixes-for-v6.15-rc2' of git://git.kernel.org/pub/scm/linux/kernel/git/brgl/linux
Pull gpio fixes from Bartosz Golaszewski:
- fix resource handling in gpio-tegra186
- fix wakeup source leaks in gpio-mpc8xxx and gpio-zynq
- fix minor issues with some GPIO OF quirks
- deprecate GPIOD_FLAGS_BIT_NONEXCLUSIVE and devm_gpiod_unhinge()
symbols and add a TODO task to track replacing them with a better
solution
* tag 'gpio-fixes-for-v6.15-rc2' of git://git.kernel.org/pub/scm/linux/kernel/git/brgl/linux:
gpiolib: of: Move Atmel HSMCI quirk up out of the regulator comment
gpiolib: of: Fix the choice for Ingenic NAND quirk
gpio: zynq: Fix wakeup source leaks on device unbind
gpio: mpc8xxx: Fix wakeup source leaks on device unbind
gpio: TODO: track the removal of regulator-related workarounds
MAINTAINERS: add more keywords for the GPIO subsystem entry
gpio: deprecate devm_gpiod_unhinge()
gpio: deprecate the GPIOD_FLAGS_BIT_NONEXCLUSIVE flag
gpio: tegra186: fix resource handling in ACPI probe path
Merge tag 'mtd/fixes-for-6.15-rc2' of git://git.kernel.org/pub/scm/linux/kernel/git/mtd/linux
Pull mtd fixes from Miquel Raynal:
"Two important fixes: the build of the SPI NAND layer with old GCC
versions as well as the fix of the Qpic Makefile which was wrong in
the first place.
There are also two smaller fixes about a missing error and status
check"
* tag 'mtd/fixes-for-6.15-rc2' of git://git.kernel.org/pub/scm/linux/kernel/git/mtd/linux:
mtd: spinand: Fix build with gcc < 7.5
mtd: rawnand: Add status chack in r852_ready()
mtd: inftlcore: Add error check for inftl_read_oob()
mtd: nand: Drop explicit test for built-in CONFIG_SPI_QPIC_SNAND
The 'read_write_len_ext' field in 'struct ethtool_cmis_cdb_cmd_args'
stores the maximum number of bytes that can be read from or written to
the Local Payload (LPL) page in a single multi-byte access.
Cited commit started overwriting this field with the maximum number of
bytes that can be read from or written to the Extended Payload (LPL)
pages in a single multi-byte access. Transceiver modules that support
auto paging can advertise a number larger than 255 which is problematic
as 'read_write_len_ext' is a 'u8', resulting in the number getting
truncated and firmware flashing failing [1].
Fix by ignoring the maximum EPL access size as the kernel does not
currently support auto paging (even if the transceiver module does) and
will not try to read / write more than 128 bytes at once.
[1]
Transceiver module firmware flashing started for device enp177s0np0
Transceiver module firmware flashing in progress for device enp177s0np0
Progress: 0%
Transceiver module firmware flashing encountered an error for device enp177s0np0
Status message: Write FW block EPL command failed, LPL length is longer
than CDB read write length extension allows.
Fixes: 9a3b0d078bd8 ("net: ethtool: Add support for writing firmware blocks using EPL payload") Reported-by: Damodharam Ammepalli <damodharam.ammepalli@broadcom.com> Closes: https://lore.kernel.org/netdev/20250402183123.321036-3-michael.chan@broadcom.com/ Tested-by: Damodharam Ammepalli <damodharam.ammepalli@broadcom.com> Signed-off-by: Ido Schimmel <idosch@nvidia.com> Reviewed-by: Damodharam Ammepalli <damodharam.ammepalli@broadcom.com> Reviewed-by: Petr Machata <petrm@nvidia.com> Link: https://patch.msgid.link/20250409112440.365672-1-idosch@nvidia.com Signed-off-by: Paolo Abeni <pabeni@redhat.com>
Paolo Abeni [Thu, 10 Apr 2025 11:13:35 +0000 (13:13 +0200)]
Merge tag 'nf-25-04-10' of git://git.kernel.org/pub/scm/linux/kernel/git/netfilter/nf
Pablo Neira Ayuso says:
====================
Netfilter fixes for net
The following batch contains a Netfilter fix and improved test coverage:
1) Fix AVX2 matching in nft_pipapo, from Florian Westphal.
2) Extend existing test to improve coverage for the aforementioned bug,
also from Florian.
netfilter pull request 25-04-10
* tag 'nf-25-04-10' of git://git.kernel.org/pub/scm/linux/kernel/git/netfilter/nf:
selftests: netfilter: add test case for recent mismatch bug
nft_set_pipapo: fix incorrect avx2 match of 5th field octet
====================
selftests: netfilter: add test case for recent mismatch bug
Without 'nft_set_pipapo: fix incorrect avx2 match of 5th field octet"
this fails:
TEST: reported issues
Add two elements, flush, re-add 1s [ OK ]
net,mac with reload 0s [ OK ]
net,port,proto 3s [ OK ]
avx2 false match 0s [FAIL]
False match for fe80:dead:01fe:0a02:0b03:6007:8009:a001
Other tests do not detect the kernel bug as they only alter parts in
the /64 netmask.
nft_set_pipapo: fix incorrect avx2 match of 5th field octet
Given a set element like:
icmpv6 . dead:beef:00ff::1
The value of 'ff' is irrelevant, any address will be matched
as long as the other octets are the same.
This is because of too-early register clobbering:
ymm7 is reloaded with new packet data (pkt[9]) but it still holds data
of an earlier load that wasn't processed yet.
The existing tests in nft_concat_range.sh selftests do exercise this code
path, but do not trigger incorrect matching due to the network prefix
limitation.
net: ppp: Add bound checking for skb data on ppp_sync_txmung
Ensure we have enough data in linear buffer from skb before accessing
initial bytes. This prevents potential out-of-bounds accesses
when processing short packets.
When ppp_sync_txmung receives an incoming package with an empty
payload:
(remote) gef➤ p *(struct pppoe_hdr *) (skb->head + skb->network_header)
$18 = {
type = 0x1,
ver = 0x1,
code = 0x0,
sid = 0x2,
length = 0x0,
tag = 0xffff8880371cdb96
}
from the skb struct (trimmed)
tail = 0x16,
end = 0x140,
head = 0xffff88803346f400 "4",
data = 0xffff88803346f416 ":\377",
truesize = 0x380,
len = 0x0,
data_len = 0x0,
mac_len = 0xe,
hdr_len = 0x0,
Peng Jiang [Mon, 24 Mar 2025 11:12:30 +0000 (19:12 +0800)]
vdso: Address variable shadowing in macros
Compiling the kernel with gcc12.3 W=2 results in shadowing warnings:
warning: declaration of '__pptr' shadows a previous local [-Wshadow]
const struct { type x; } __packed *__pptr = (typeof(__pptr))(ptr);
note: in definition of macro '__put_unaligned_t'
__pptr->x = (val);
note: in expansion of macro '__get_unaligned_t'
__put_unaligned_t(type, __get_unaligned_t(type, src), dst);
__get_unaligned_t() and __put_unaligned_t() use a local variable named
'__pptr', which can lead to variable shadowing when these macros are used in
the same scope. This results in a -Wshadow warning during compilation.
To address this issue, rename the local variables within the macros to
ensure uniqueness.
net: Fix null-ptr-deref by sock_lock_init_class_and_name() and rmmod.
When I ran the repro [0] and waited a few seconds, I observed two
LOCKDEP splats: a warning immediately followed by a null-ptr-deref. [1]
Reproduction Steps:
1) Mount CIFS
2) Add an iptables rule to drop incoming FIN packets for CIFS
3) Unmount CIFS
4) Unload the CIFS module
5) Remove the iptables rule
At step 3), the CIFS module calls sock_release() for the underlying
TCP socket, and it returns quickly. However, the socket remains in
FIN_WAIT_1 because incoming FIN packets are dropped.
At this point, the module's refcnt is 0 while the socket is still
alive, so the following rmmod command succeeds.
# ss -tan
State Recv-Q Send-Q Local Address:Port Peer Address:Port
FIN-WAIT-1 0 477 10.0.2.15:51062 10.0.0.137:445
This highlights a discrepancy between the lifetime of the CIFS module
and the underlying TCP socket. Even after CIFS calls sock_release()
and it returns, the TCP socket does not die immediately in order to
close the connection gracefully.
While this is generally fine, it causes an issue with LOCKDEP because
CIFS assigns a different lock class to the TCP socket's sk->sk_lock
using sock_lock_init_class_and_name().
Once an incoming packet is processed for the socket or a timer fires,
sk->sk_lock is acquired.
Then, LOCKDEP checks the lock context in check_wait_context(), where
hlock_class() is called to retrieve the lock class. However, since
the module has already been unloaded, hlock_class() logs a warning
and returns NULL, triggering the null-ptr-deref.
If LOCKDEP is enabled, we must ensure that a module calling
sock_lock_init_class_and_name() (CIFS, NFS, etc) cannot be unloaded
while such a socket is still alive to prevent this issue.
Let's hold the module reference in sock_lock_init_class_and_name()
and release it when the socket is freed in sk_prot_free().
Note that sock_lock_init() clears sk->sk_owner for svc_create_socket()
that calls sock_lock_init_class_and_name() for a listening socket,
which clones a socket by sk_clone_lock() without GFP_ZERO.
ipv6: Align behavior across nexthops during path selection
A nexthop is only chosen when the calculated multipath hash falls in the
nexthop's hash region (i.e., the hash is smaller than the nexthop's hash
threshold) and when the nexthop is assigned a non-negative score by
rt6_score_route().
Commit 4d0ab3a6885e ("ipv6: Start path selection from the first
nexthop") introduced an unintentional difference between the first
nexthop and the rest when the score is negative.
When the first nexthop matches, but has a negative score, the code will
currently evaluate subsequent nexthops until one is found with a
non-negative score. On the other hand, when a different nexthop matches,
but has a negative score, the code will fallback to the nexthop with
which the selection started ('match').
Align the behavior across all nexthops and fallback to 'match' when the
first nexthop matches, but has a negative score.
Fixes: 3d709f69a3e7 ("ipv6: Use hash-threshold instead of modulo-N") Fixes: 4d0ab3a6885e ("ipv6: Start path selection from the first nexthop") Reported-by: Willem de Bruijn <willemdebruijn.kernel@gmail.com> Closes: https://lore.kernel.org/netdev/67efef607bc41_1ddca82948c@willemb.c.googlers.com.notmuch/ Signed-off-by: Ido Schimmel <idosch@nvidia.com> Reviewed-by: Willem de Bruijn <willemb@google.com> Reviewed-by: David Ahern <dsahern@kernel.org> Link: https://patch.msgid.link/20250408084316.243559-1-idosch@nvidia.com Signed-off-by: Jakub Kicinski <kuba@kernel.org>
Vladimir Oltean [Mon, 7 Apr 2025 09:40:42 +0000 (12:40 +0300)]
net: phy: allow MDIO bus PM ops to start/stop state machine for phylink-controlled PHY
DSA has 2 kinds of drivers:
1. Those who call dsa_switch_suspend() and dsa_switch_resume() from
their device PM ops: qca8k-8xxx, bcm_sf2, microchip ksz
2. Those who don't: all others. The above methods should be optional.
For type 1, dsa_switch_suspend() calls dsa_user_suspend() -> phylink_stop(),
and dsa_switch_resume() calls dsa_user_resume() -> phylink_start().
These seem good candidates for setting mac_managed_pm = true because
that is essentially its definition [1], but that does not seem to be the
biggest problem for now, and is not what this change focuses on.
Talking strictly about the 2nd category of DSA drivers here (which
do not have MAC managed PM, meaning that for their attached PHYs,
mdio_bus_phy_suspend() and mdio_bus_phy_resume() should run in full),
I have noticed that the following warning from mdio_bus_phy_resume() is
triggered:
It's running as a result of a previous dsa_user_open() -> ... ->
phylink_start() -> phy_start() having been initiated by the user.
The previous mdio_bus_phy_suspend() was supposed to have called
phy_stop_machine(), but it didn't. So this is why the PHY is in state
PHY_NOLINK by the time mdio_bus_phy_resume() runs.
mdio_bus_phy_suspend() did not call phy_stop_machine() because for
phylink, the phydev->adjust_link function pointer is NULL. This seems a
technicality introduced by commit fddd91016d16 ("phylib: fix PAL state
machine restart on resume"). That commit was written before phylink
existed, and was intended to avoid crashing with consumer drivers which
don't use the PHY state machine - phylink always does, when using a PHY.
But phylink itself has historically not been developed with
suspend/resume in mind, and apparently not tested too much in that
scenario, allowing this bug to exist unnoticed for so long. Plus, prior
to the WARN_ON(), it would have likely been invisible.
This issue is not in fact restricted to type 2 DSA drivers (according to
the above ad-hoc classification), but can be extrapolated to any MAC
driver with phylink and MDIO-bus-managed PHY PM ops. DSA is just where
the issue was reported. Assuming mac_managed_pm is set correctly, a
quick search indicates the following other drivers might be affected:
Make the existing conditions dependent on the PHY device having a
phydev->phy_link_change() implementation equal to the default
phy_link_change() provided by phylib. Otherwise, we implicitly know that
the phydev has the phylink-provided phylink_phy_change() callback, and
when phylink is used, the PHY state machine always needs to be stopped/
started on the suspend/resume path. The code is structured as such that
if phydev->phy_link_change() is absent, it is a matter of time until the
kernel will crash - no need to further complicate the test.
Thus, for the situation where the PM is not managed by the MAC, we will
make the MDIO bus PM ops treat identically the phylink-controlled PHYs
with the phylib-controlled PHYs where an adjust_link() callback is
supplied. In both cases, the MDIO bus PM ops should stop and restart the
PHY state machine.
Vladimir Oltean [Mon, 7 Apr 2025 09:38:59 +0000 (12:38 +0300)]
net: phy: move phy_link_change() prior to mdio_bus_phy_may_suspend()
In an upcoming change, mdio_bus_phy_may_suspend() will need to
distinguish a phylib-based PHY client from a phylink PHY client.
For that, it will need to compare the phydev->phy_link_change() function
pointer with the eponymous phy_link_change() provided by phylib.
To avoid forward function declarations, the default PHY link state
change method should be moved upwards. There is no functional change
associated with this patch, it is only to reduce the noise from a real
bug fix.
Merge tag 'linux_kselftest-fixes-6.15-rc2' of git://git.kernel.org/pub/scm/linux/kernel/git/shuah/linux-kselftest
Pull kselftest fixes from Shuah Khan:
- Fixes tpm2, futex, and mincore tests
- Create a dedicated .gitignore for tpm2 tests
* tag 'linux_kselftest-fixes-6.15-rc2' of git://git.kernel.org/pub/scm/linux/kernel/git/shuah/linux-kselftest:
selftests/mincore: Allow read-ahead pages to reach the end of the file
selftests/futex: futex_waitv wouldblock test should fail
selftests: tpm2: test_smoke: use POSIX-conformant expression operator
selftests: tpm2: create a dedicated .gitignore
Sebastian Andrzej Siewior [Fri, 4 Apr 2025 13:34:29 +0000 (15:34 +0200)]
timekeeping: Add a lockdep override in tick_freeze()
tick_freeze() acquires a raw spinlock (tick_freeze_lock). Later in the
callchain (timekeeping_suspend() -> mc146818_avoid_UIP()) the RTC driver
acquires a spinlock which becomes a sleeping lock on PREEMPT_RT. Lockdep
complains about this lock nesting.
Add a lockdep override for this special case and a comment explaining
why it is okay.
Reported-by: Borislav Petkov <bp@alien8.de> Reported-by: Chris Bainbridge <chris.bainbridge@gmail.com> Signed-off-by: Sebastian Andrzej Siewior <bigeasy@linutronix.de> Signed-off-by: Thomas Gleixner <tglx@linutronix.de> Acked-by: Peter Zijlstra (Intel) <peterz@infradead.org> Link: https://lore.kernel.org/all/20250404133429.pnAzf-eF@linutronix.de Closes: https://lore.kernel.org/all/20250330113202.GAZ-krsjAnurOlTcp-@fat_crate.local/ Closes: https://lore.kernel.org/all/CAP-bSRZ0CWyZZsMtx046YV8L28LhY0fson2g4EqcwRAVN1Jk+Q@mail.gmail.com/
Nam Cao [Tue, 8 Apr 2025 10:38:54 +0000 (12:38 +0200)]
hrtimer: Add missing ACCESS_PRIVATE() for hrtimer::function
The "function" field of struct hrtimer has been changed to private, but
two instances have not been converted to use ACCESS_PRIVATE().
Convert them to use ACCESS_PRIVATE().
Fixes: 04257da0c99c ("hrtimers: Make callback function pointer private") Reported-by: kernel test robot <lkp@intel.com> Signed-off-by: Nam Cao <namcao@linutronix.de> Signed-off-by: Thomas Gleixner <tglx@linutronix.de> Link: https://lore.kernel.org/all/20250408103854.1851093-1-namcao@linutronix.de Closes: https://lore.kernel.org/oe-kbuild-all/202504071931.vOVl13tt-lkp@intel.com/ Closes: https://lore.kernel.org/oe-kbuild-all/202504072155.5UAZjYGU-lkp@intel.com/
Dave Hansen [Wed, 9 Apr 2025 13:58:37 +0000 (06:58 -0700)]
x86/cpu: Avoid running off the end of an AMD erratum table
The NULL array terminator at the end of erratum_1386_microcode was
removed during the switch from x86_cpu_desc to x86_cpu_id. This
causes readers to run off the end of the array.
Replace the NULL.
Fixes: f3f325152673 ("x86/cpu: Move AMD erratum 1386 table over to 'x86_cpu_id'") Reported-by: Jiri Slaby <jirislaby@kernel.org> Signed-off-by: Dave Hansen <dave.hansen@linux.intel.com>
ublk: pass ublksrv_ctrl_cmd * instead of io_uring_cmd *
The ublk_ctrl_*() handlers all take struct io_uring_cmd *cmd but only
use it to get struct ublksrv_ctrl_cmd *header from the io_uring SQE.
Since the caller ublk_ctrl_uring_cmd() has already computed header, pass
it instead of cmd.
Ming Lei [Wed, 9 Apr 2025 01:14:42 +0000 (09:14 +0800)]
ublk: don't fail request for recovery & reissue in case of ubq->canceling
ubq->canceling is set with request queue quiesced when io_uring context is
exiting. USER_RECOVERY or !RECOVERY_FAIL_IO requires request to be re-queued
and re-dispatch after device is recovered.
However commit d796cea7b9f3 ("ublk: implement ->queue_rqs()") still may fail
any request in case of ubq->canceling, this way breaks USER_RECOVERY or
!RECOVERY_FAIL_IO.
Fix it by calling __ublk_abort_rq() in case of ubq->canceling.
Ming Lei [Wed, 9 Apr 2025 01:14:41 +0000 (09:14 +0800)]
ublk: fix handling recovery & reissue in ublk_abort_queue()
Commit 8284066946e6 ("ublk: grab request reference when the request is handled
by userspace") doesn't grab request reference in case of recovery reissue.
Then the request can be requeued & re-dispatch & failed when canceling
uring command.
If it is one zc request, the request can be freed before io_uring
returns the zc buffer back, then cause kernel panic:
Fixes it by always grabbing request reference for aborting the request.
Reported-by: Caleb Sander Mateos <csander@purestorage.com> Closes: https://lore.kernel.org/linux-block/CADUfDZodKfOGUeWrnAxcZiLT+puaZX8jDHoj_sfHZCOZwhzz6A@mail.gmail.com/ Fixes: 8284066946e6 ("ublk: grab request reference when the request is handled by userspace") Signed-off-by: Ming Lei <ming.lei@redhat.com> Link: https://lore.kernel.org/r/20250409011444.2142010-2-ming.lei@redhat.com Signed-off-by: Jens Axboe <axboe@kernel.dk>
As a limit of 1 is invalid, this patch series moves the limit
validation to after all configuration changes have been done. To do
so, the configuration is done in a temporary work area then applied to
the internal state.
The patch series also adds new test cases.
v3:
- remove a couple of unnecessary comments
- rearrange local variables to use reverse Christmas tree style
declaration order
v2: https://lore.kernel.org/all/20250402162750.1671155-1-tavip@google.com/
- remove tmp struct and directly use local variables
selftests/tc-testing: sfq: check that a derived limit of 1 is rejected
Because the limit is updated indirectly when other parameters are
updated, there are cases where even though the user requests a limit
of 2 it can actually be set to 1.
Add the following test cases to check that the kernel rejects them:
- limit 2 depth 1 flows 1
- limit 2 depth 1 divisor 1
Signed-off-by: Octavian Purdila <tavip@google.com> Acked-by: Cong Wang <xiyou.wangcong@gmail.com> Signed-off-by: David S. Miller <davem@davemloft.net>
It is not sufficient to directly validate the limit on the data that
the user passes as it can be updated based on how the other parameters
are changed.
Move the check at the end of the configuration update process to also
catch scenarios where the limit is indirectly updated, for example
with the following configurations:
net_sched: sch_sfq: use a temporary work area for validating configuration
Many configuration parameters have influence on others (e.g. divisor
-> flows -> limit, depth -> limit) and so it is difficult to correctly
do all of the validation before applying the configuration. And if a
validation error is detected late it is difficult to roll back a
partially applied configuration.
To avoid these issues use a temporary work area to update and validate
the configuration and only then apply the configuration to the
internal state.
Signed-off-by: Octavian Purdila <tavip@google.com> Acked-by: Cong Wang <xiyou.wangcong@gmail.com> Signed-off-by: David S. Miller <davem@davemloft.net>
Create a document to summarize hard-earned knowledge about RSB-related
mitigations, with references, and replace the overly verbose yet
incomplete comments with a reference to the document.
x86/bugs: Don't fill RSB on context switch with eIBRS
User->user Spectre v2 attacks (including RSB) across context switches
are already mitigated by IBPB in cond_mitigation(), if enabled globally
or if either the prev or the next task has opted in to protection. RSB
filling without IBPB serves no purpose for protecting user space, as
indirect branches are still vulnerable.
User->kernel RSB attacks are mitigated by eIBRS. In which case the RSB
filling on context switch isn't needed, so remove it.
Suggested-by: Pawan Gupta <pawan.kumar.gupta@linux.intel.com> Signed-off-by: Josh Poimboeuf <jpoimboe@kernel.org> Signed-off-by: Ingo Molnar <mingo@kernel.org> Reviewed-by: Pawan Gupta <pawan.kumar.gupta@linux.intel.com> Reviewed-by: Amit Shah <amit.shah@amd.com> Reviewed-by: Nikolay Borisov <nik.borisov@suse.com> Link: https://lore.kernel.org/r/98cdefe42180358efebf78e3b80752850c7a3e1b.1744148254.git.jpoimboe@kernel.org
x86/bugs: Don't fill RSB on VMEXIT with eIBRS+retpoline
eIBRS protects against guest->host RSB underflow/poisoning attacks.
Adding retpoline to the mix doesn't change that. Retpoline has a
balanced CALL/RET anyway.
So the current full RSB filling on VMEXIT with eIBRS+retpoline is
overkill. Disable it or do the VMEXIT_LITE mitigation if needed.
Suggested-by: Pawan Gupta <pawan.kumar.gupta@linux.intel.com> Signed-off-by: Josh Poimboeuf <jpoimboe@kernel.org> Signed-off-by: Ingo Molnar <mingo@kernel.org> Reviewed-by: Pawan Gupta <pawan.kumar.gupta@linux.intel.com> Reviewed-by: Amit Shah <amit.shah@amd.com> Reviewed-by: Nikolay Borisov <nik.borisov@suse.com> Cc: Paolo Bonzini <pbonzini@redhat.com> Cc: Vitaly Kuznetsov <vkuznets@redhat.com> Cc: Sean Christopherson <seanjc@google.com> Cc: David Woodhouse <dwmw2@infradead.org> Link: https://lore.kernel.org/r/84a1226e5c9e2698eae1b5ade861f1b8bf3677dc.1744148254.git.jpoimboe@kernel.org
x86/bugs: Fix RSB clearing in indirect_branch_prediction_barrier()
IBPB is expected to clear the RSB. However, if X86_BUG_IBPB_NO_RET is
set, that doesn't happen. Make indirect_branch_prediction_barrier()
take that into account by calling write_ibpb() which clears RSB on
X86_BUG_IBPB_NO_RET:
write_ibpb() does IBPB, which (among other things) flushes branch type
predictions on AMD. If the CPU has SRSO_NO, or if the SRSO mitigation
has been disabled, branch type flushing isn't needed, in which case the
lighter-weight SBPB can be used.
The 'x86_pred_cmd' variable already keeps track of whether IBPB or SBPB
should be used. Use that instead of hardcoding IBPB.
Andy Shevchenko [Mon, 7 Apr 2025 17:22:14 +0000 (20:22 +0300)]
x86/early_printk: Use 'mmio32' for consistency, fix comments
First of all, using 'mmio' prevents proper implementation of 8-bit accessors.
Second, it's simply inconsistent with uart8250 set of options. Rename it to
'mmio32'. While at it, remove rather misleading comment in the documentation.
From now on mmio32 is self-explanatory and pciserial supports not only 32-bit
MMIO accessors.
Also, while at it, fix the comment for the "pciserial" case. The comment
seems to be a copy'n'paste error when mentioning "serial" instead of
"pciserial" (with double quotes). Fix this.
With that, move it upper, so we don't calculate 'buf' twice.
James Morse [Mon, 7 Apr 2025 12:46:37 +0000 (13:46 +0100)]
x86/resctrl: Fix rdtgroup_mkdir()'s unlocked use of kernfs_node::name
Since
741c10b096bc ("kernfs: Use RCU to access kernfs_node::name.")
a helper rdt_kn_name() that checks that rdtgroup_mutex is held has been used
for all accesses to the kernfs node name.
rdtgroup_mkdir() uses the name to determine if a valid monitor group is being
created by checking the parent name is "mon_groups". This is done without
holding rdtgroup_mutex, and now triggers the following warning:
Creating a control or monitor group calls mkdir_rdt_prepare(), which uses
rdtgroup_kn_lock_live() to take the rdtgroup_mutex.
To avoid taking and dropping the lock, move the check for the monitor group
name and position into mkdir_rdt_prepare() so that it occurs under
rdtgroup_mutex. Hoist is_mon_groups() earlier in the file.
[ bp: Massage. ]
Fixes: 741c10b096bc ("kernfs: Use RCU to access kernfs_node::name.") Signed-off-by: James Morse <james.morse@arm.com> Signed-off-by: Borislav Petkov (AMD) <bp@alien8.de> Reviewed-by: Reinette Chatre <reinette.chatre@intel.com> Acked-by: Ingo Molnar <mingo@kernel.org> Link: https://lore.kernel.org/r/20250407124637.2433230-1-james.morse@arm.com
Merge tag 'linux_kselftest-kunit-6.15-rc2' of git://git.kernel.org/pub/scm/linux/kernel/git/shuah/linux-kselftest
Pull kunit fixes from Shuah Khan:
- Fix the tool to report test count in case of a late test plan when
tests are specified before the test plan
- Fix spelling error
* tag 'linux_kselftest-kunit-6.15-rc2' of git://git.kernel.org/pub/scm/linux/kernel/git/shuah/linux-kselftest:
kunit: Spelling s/slowm/slow/
kunit: tool: fix count of tests if late test plan
page_pool_dev_alloc_pages could return NULL. There was a WARN_ON(!page)
but it would still proceed to use the NULL pointer and then crash.
This is similar to commit 001ba0902046
("net: fec: handle page_pool_dev_alloc_pages error").
This is found by our static analysis tool KNighter.
Signed-off-by: Chenyuan Yang <chenyuan0y@gmail.com> Fixes: 3c47e8ae113a ("net: libwx: Support to receive packets in NAPI") Reviewed-by: Joe Damato <jdamato@fastly.com> Link: https://patch.msgid.link/20250407184952.2111299-1-chenyuan0y@gmail.com Signed-off-by: Jakub Kicinski <kuba@kernel.org>
The parent commit fixes an issue around these counters where one of them
-- MPJoinAckHMacFailure -- was wrongly incremented in some cases.
This makes sure the counter is always 0. It should be incremented only
in case of corruption, or a wrong implementation, which should not be
the case in these selftests.
mptcp: only inc MPJoinAckHMacFailure for HMAC failures
Recently, during a debugging session using local MPTCP connections, I
noticed MPJoinAckHMacFailure was not zero on the server side. The
counter was in fact incremented when the PM rejected new subflows,
because the 'subflow' limit was reached.
The fix is easy, simply dissociating the two cases: only the HMAC
validation check should increase MPTCP_MIB_JOINACKMAC counter.
Fixes: 4cf8b7e48a09 ("subflow: introduce and use mptcp_can_accept_new_subflow()") Cc: stable@vger.kernel.org Reviewed-by: Geliang Tang <geliang@kernel.org> Signed-off-by: Matthieu Baerts (NGI0) <matttbe@kernel.org> Reviewed-by: Simon Horman <horms@kernel.org> Link: https://patch.msgid.link/20250407-net-mptcp-hmac-failure-mib-v1-1-3c9ecd0a3a50@kernel.org Signed-off-by: Jakub Kicinski <kuba@kernel.org>
Qiuxu Zhuo [Tue, 11 Mar 2025 08:09:40 +0000 (16:09 +0800)]
selftests/mincore: Allow read-ahead pages to reach the end of the file
When running the mincore_selftest on a system with an XFS file system, it
failed the "check_file_mmap" test case due to the read-ahead pages reaching
the end of the file. The failure log is as below:
RUN global.check_file_mmap ...
mincore_selftest.c:264:check_file_mmap:Expected i (1024) < vec_size (1024)
mincore_selftest.c:265:check_file_mmap:Read-ahead pages reached the end of the file
check_file_mmap: Test failed
FAIL global.check_file_mmap
This is because the read-ahead window size of the XFS file system on this
machine is 4 MB, which is larger than the size from the #PF address to the
end of the file. As a result, all the pages for this file are populated.
This issue can be fixed by extending the current FILE_SIZE 4MB to a larger
number, but it will still fail if the read-ahead window size of the file
system is larger enough. Additionally, in the real world, read-ahead pages
reaching the end of the file can happen and is an expected behavior.
Therefore, allowing read-ahead pages to reach the end of the file is a
better choice for the "check_file_mmap" test case.
Ahmed Salem [Tue, 11 Feb 2025 23:16:17 +0000 (01:16 +0200)]
selftests: tpm2: test_smoke: use POSIX-conformant expression operator
Use POSIX-conformant expression operator symbol '='.
The use of the non POSIX-conformant symbol '==' would work
in bash, but not in sh where the unexpected operator error
would result in test_smoke.sh being skipped.
Instead of changing the shebang to use bash, which may not be
available on all systems, use the POSIX-conformant expression
symbol '=' to test for equality.
Without this patch:
===================
# make -j8 TARGETS=tpm2 kselftest
# selftests: tpm2: test_smoke.sh
# ./test_smoke.sh: 9: [: 2: unexpected operator
ok 1 selftests: tpm2: test_smoke.sh # SKIP
With this patch:
================
# make -j8 TARGETS=tpm2 kselftest
# selftests: tpm2: test_smoke.sh
# Ran 9 tests in 9.236s
ok 1 selftests: tpm2: test_smoke.sh
Khaled Elnaggar [Sun, 26 Jan 2025 19:51:33 +0000 (21:51 +0200)]
selftests: tpm2: create a dedicated .gitignore
The tpm2 selftests produce two logs: SpaceTest.log and
AsyncTest.log. Only SpaceTest.log was listed in selftests/.gitignore,
while AsyncTest.log remained untracked.
This change creates a dedicated .gitignore in the tpm2/ directory to
manage these entries, keeping tpm2-specific patterns isolated from
parent .gitignore.
Fixed white-space errors during commit
Shuah Khan <skhan@linuxfoundation.org>
Merge tag 'for-linus' of git://git.kernel.org/pub/scm/virt/kvm/kvm
Pull kvm fixes from Paolo Bonzini:
"ARM:
- Rework heuristics for resolving the fault IPA (HPFAR_EL2 v. re-walk
stage-1 page tables) to align with the architecture. This avoids
possibly taking an SEA at EL2 on the page table walk or using an
architecturally UNKNOWN fault IPA
- Use acquire/release semantics in the KVM FF-A proxy to avoid
reading a stale value for the FF-A version
- Fix KVM guest driver to match PV CPUID hypercall ABI
- Use Inner Shareable Normal Write-Back mappings at stage-1 in KVM
selftests, which is the only memory type for which atomic
instructions are architecturally guaranteed to work
s390:
- Don't use %pK for debug printing and tracepoints
x86:
- Use a separate subclass when acquiring KVM's per-CPU posted
interrupts wakeup lock in the scheduled out path, i.e. when adding
a vCPU on the list of vCPUs to wake, to workaround a false positive
deadlock. The schedule out code runs with a scheduler lock that the
wakeup handler takes in the opposite order; but it does so with
IRQs disabled and cannot run concurrently with a wakeup
- Allow building irqbypass.ko as as module when kvm.ko is a module
- Wrap relatively expensive sanity check with KVM_PROVE_MMU
- Acquire SRCU in KVM_GET_MP_STATE to protect guest memory accesses
selftests:
- Add more scenarios to the MONITOR/MWAIT test
- Add option to rseq test to override /dev/cpu_dma_latency
- Bring list of exit reasons up to date
- Cleanup Makefile to list once tests that are valid on all
architectures
Other:
- Documentation fixes"
* tag 'for-linus' of git://git.kernel.org/pub/scm/virt/kvm/kvm: (26 commits)
KVM: arm64: Use acquire/release to communicate FF-A version negotiation
KVM: arm64: selftests: Explicitly set the page attrs to Inner-Shareable
KVM: arm64: selftests: Introduce and use hardware-definition macros
KVM: VMX: Use separate subclasses for PI wakeup lock to squash false positive
KVM: VMX: Assert that IRQs are disabled when putting vCPU on PI wakeup list
KVM: x86: Explicitly zero-initialize on-stack CPUID unions
KVM: Allow building irqbypass.ko as as module when kvm.ko is a module
KVM: x86/mmu: Wrap sanity check on number of TDP MMU pages with KVM_PROVE_MMU
KVM: selftests: Add option to rseq test to override /dev/cpu_dma_latency
KVM: x86: Acquire SRCU in KVM_GET_MP_STATE to protect guest memory accesses
Documentation: kvm: remove KVM_CAP_MIPS_TE
Documentation: kvm: organize capabilities in the right section
Documentation: kvm: fix some definition lists
Documentation: kvm: drop "Capability" heading from capabilities
Documentation: kvm: give correct name for KVM_CAP_SPAPR_MULTITCE
Documentation: KVM: KVM_GET_SUPPORTED_CPUID now exposes TSC_DEADLINE
selftests: kvm: list once tests that are valid on all architectures
selftests: kvm: bring list of exit reasons up to date
selftests: kvm: revamp MONITOR/MWAIT tests
KVM: arm64: Don't translate FAR if invalid/unsafe
...
objtool: Remove ANNOTATE_IGNORE_ALTERNATIVE from CLAC/STAC
ANNOTATE_IGNORE_ALTERNATIVE adds additional noise to the code generated
by CLAC/STAC alternatives, hurting readability for those whose read
uaccess-related code generation on a regular basis.
Remove the annotation specifically for the "NOP patched with CLAC/STAC"
case in favor of a manual check.
Leave the other uses of that annotation in place as they're less common
and more difficult to detect.
Merge tag 'probes-fixes-v6.14' of git://git.kernel.org/pub/scm/linux/kernel/git/trace/linux-trace
Pull probes fixes from Masami Hiramatsu:
- fprobe: remove fprobe_hlist_node when module unloading
When a fprobe target module is removed, the fprobe_hlist_node should
be removed from the fprobe's hash table to prevent reusing
accidentally if another module is loaded at the same address.
- fprobe: lock module while registering fprobe
The module containing the function to be probeed is locked using a
reference counter until the fprobe registration is complete, which
prevents use after free.
- fprobe-events: fix possible UAF on modules
Basically as same as above, but in the fprobe-events layer we also
need to get module reference counter when we find the tracepoint in
the module.
* tag 'probes-fixes-v6.14' of git://git.kernel.org/pub/scm/linux/kernel/git/trace/linux-trace:
tracing: fprobe: Cleanup fprobe hash when module unloading
tracing: fprobe events: Fix possible UAF on modules
tracing: fprobe: Fix to lock module while registering fprobe
rtnetlink: Fix bad unlock balance in do_setlink().
When validate_linkmsg() fails in do_setlink(), we jump to the errout
label and calls netdev_unlock_ops() even though we have not called
netdev_lock_ops() as reported by syzbot. [0]
syz-executor814/5834 is trying to release lock (&dev_instance_lock_key) at:
[<ffffffff89f41f56>] netdev_unlock include/linux/netdevice.h:2756 [inline]
[<ffffffff89f41f56>] netdev_unlock_ops include/net/netdev_lock.h:48 [inline]
[<ffffffff89f41f56>] do_setlink+0xc26/0x43a0 net/core/rtnetlink.c:3406
but there are no more locks to release!
other info that might help us debug this:
1 lock held by syz-executor814/5834:
#0: ffffffff900fc408 (rtnl_mutex){+.+.}-{4:4}, at: rtnl_lock net/core/rtnetlink.c:80 [inline]
#0: ffffffff900fc408 (rtnl_mutex){+.+.}-{4:4}, at: rtnl_nets_lock net/core/rtnetlink.c:341 [inline]
#0: ffffffff900fc408 (rtnl_mutex){+.+.}-{4:4}, at: rtnl_newlink+0xd68/0x1fe0 net/core/rtnetlink.c:4064
Merge tag 'cgroup-for-6.15-rc1-fixes' of git://git.kernel.org/pub/scm/linux/kernel/git/tj/cgroup
Pull cgroup fixes from Tejun Heo:
- A number of cpuset remote partition related fixes and cleanups along
with selftest updates.
- A change from this merge window made cgroup_rstat_updated_list()
called outside cgroup_rstat_lock leading to list corruptions. Fix it
by relocating the call inside the lock.
* tag 'cgroup-for-6.15-rc1-fixes' of git://git.kernel.org/pub/scm/linux/kernel/git/tj/cgroup:
cgroup/cpuset: Fix race between newly created partition and dying one
cgroup: rstat: call cgroup_rstat_updated_list with cgroup_rstat_lock
selftest/cgroup: Add a remote partition transition test to test_cpuset_prs.sh
selftest/cgroup: Clean up and restructure test_cpuset_prs.sh
selftest/cgroup: Update test_cpuset_prs.sh to use | as effective CPUs and state separator
cgroup/cpuset: Remove unneeded goto in sched_partition_write() and rename it
cgroup/cpuset: Code cleanup and comment update
cgroup/cpuset: Don't allow creation of local partition over a remote one
cgroup/cpuset: Remove remote_partition_check() & make update_cpumasks_hier() handle remote partition
cgroup/cpuset: Fix error handling in remote_partition_disable()
cgroup/cpuset: Fix incorrect isolated_cpus update in update_parent_effective_cpumask()
Merge tag 'crc-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/ebiggers/linux
Pull CRC cleanups from Eric Biggers:
"Finish cleaning up the CRC kconfig options by removing the remaining
unnecessary prompts and an unnecessary 'default y', removing
CONFIG_LIBCRC32C, and documenting all the CRC library options"
* tag 'crc-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/ebiggers/linux:
lib/crc: remove CONFIG_LIBCRC32C
lib/crc: document all the CRC library kconfig options
lib/crc: remove unnecessary prompt for CONFIG_CRC_ITU_T
lib/crc: remove unnecessary prompt for CONFIG_CRC_T10DIF
lib/crc: remove unnecessary prompt for CONFIG_CRC16
lib/crc: remove unnecessary prompt for CONFIG_CRC_CCITT
lib/crc: remove unnecessary prompt for CONFIG_CRC32 and drop 'default y'
A recent optimization change in LLVM [1] aims to transform certain loop
idioms into calls to strlen() or wcslen(). This change transforms the
first while loop in UniStrcat() into a call to wcslen(), breaking the
build when UniStrcat() gets inlined into alloc_path_with_tree_prefix():
ld.lld: error: undefined symbol: wcslen
>>> referenced by nls_ucs2_utils.h:54 (fs/smb/client/../../nls/nls_ucs2_utils.h:54)
>>> vmlinux.o:(alloc_path_with_tree_prefix)
>>> referenced by nls_ucs2_utils.h:54 (fs/smb/client/../../nls/nls_ucs2_utils.h:54)
>>> vmlinux.o:(alloc_path_with_tree_prefix)
Disable this optimization with '-fno-builtin-wcslen', which prevents the
compiler from assuming that wcslen() is available in the kernel's C
library.
[ More to the point - it's not that we couldn't implement wcslen(), it's
that this isn't an optimization at all in the context of the kernel.
Replacing a simple inlined loop with a function call to the same loop
is just stupid and pointless if you don't have long strings and fancy
libraries with vectorization support etc.
For the regular 'strlen()' cases, we want the compiler to do this in
order to handle the trivial case of constant strings. And we do have
optimized versions of 'strlen()' on some architectures. But for
wcslen? Just no. - Linus ]
Once task_work_run() is running, the list of pending callbacks is
removed from the task_struct and from this point on task_work_cancel()
can't remove any pending and not yet started work items, hence the
task_work_cancel() failure and the hang on rcuwait_wait_event().
Task work could be changed to remove one work at a time, so a work
running on the current task can always cancel a pending one, however
the wait / wake design is still subject to inverted dependencies when
remote targets are involved, as pictured by Oleg:
Therefore the only option left is to acquire the event reference count
upon queueing the perf task work and release it from the task work, just
like it was done before 3a5465418f5f ("perf: Fix event leak upon exec and file release")
but without the leaks it fixed.
Some adjustments are necessary to make it work:
* A child event might dereference its parent upon freeing. Care must be
taken to release the parent last.
* Some places assuming the event doesn't have any reference held and
therefore can be freed right away must instead put the reference and
let the reference counting to its job.
Maxime Chevallier [Mon, 7 Apr 2025 13:05:10 +0000 (15:05 +0200)]
net: ethtool: Don't call .cleanup_data when prepare_data fails
There's a consistent pattern where the .cleanup_data() callback is
called when .prepare_data() fails, when it should really be called to
clean after a successful .prepare_data() as per the documentation.
Rewrite the error-handling paths to make sure we don't cleanup
un-prepared data.
Fixes: c781ff12a2f3 ("ethtool: Allow network drivers to dump arbitrary EEPROM data") Reviewed-by: Kory Maincent <kory.maincent@bootlin.com> Reviewed-by: Simon Horman <horms@kernel.org> Reviewed-by: Michal Kubecek <mkubecek@suse.cz> Signed-off-by: Maxime Chevallier <maxime.chevallier@bootlin.com> Link: https://patch.msgid.link/20250407130511.75621-1-maxime.chevallier@bootlin.com Signed-off-by: Paolo Abeni <pabeni@redhat.com>
tc: Ensure we have enough buffer space when sending filter netlink notifications
The tfilter_notify() and tfilter_del_notify() functions assume that
NLMSG_GOODSIZE is always enough to dump the filter chain. This is not
always the case, which can lead to silent notify failures (because the
return code of tfilter_notify() is not always checked). In particular,
this can lead to NLM_F_ECHO not being honoured even though an action
succeeds, which forces userspace to create workarounds[0].
Fix this by increasing the message size if dumping the filter chain into
the allocated skb fails. Use the size of the incoming skb as a size hint
if set, so we can start at a larger value when appropriate.
To trigger this, run the following commands:
# ip link add type veth
# tc qdisc replace dev veth0 root handle 1: fq_codel
# tc -echo filter add dev veth0 parent 1: u32 match u32 0 0 $(for i in $(seq 32); do echo action pedit munge ip dport set 22; done)
Before this fix, tc just returns:
Not a filter(cmd 2)
After the fix, we get the correct echo:
added filter dev veth0 parent 1: protocol all pref 49152 u32 chain 0 fh 800::800 order 2048 key ht 800 bkt 0 terminal flowid not_in_hw
match 00000000/00000000 at 0
action order 1: pedit action pass keys 1
index 1 ref 1 bind 1
key #0 at 20: val 00000016 mask ffff0000
[repeated 32 times]
WX_RXD_IPV6EX was incorrectly defined in Rx ring descriptor. In fact, this
field stores the 802.1ad ID from which the packet was received. The wrong
definition caused the statistics rx_csum_offload_errors to fail to grow
when receiving the 802.1ad packet with incorrect checksum.
x86/xen: disable CPU idle and frequency drivers for PVH dom0
When running as a PVH dom0 the ACPI tables exposed to Linux are (mostly)
the native ones, thus exposing the C and P states, that can lead to
attachment of CPU idle and frequency drivers. However the entity in
control of the CPU C and P states is Xen, as dom0 doesn't have a full view
of the system load, neither has all CPUs assigned and identity pinned.
Like it's done for classic PV guests, prevent Linux from using idle or
frequency state drivers when running as a PVH dom0.
On an AMD EPYC 7543P system without this fix a Linux PVH dom0 will keep the
host CPUs spinning at 100% even when dom0 is completely idle, as it's
attempting to use the acpi_idle driver.
Signed-off-by: Roger Pau Monné <roger.pau@citrix.com> Reviewed-by: Jason Andryuk <jason.andryuk@amd.com> Signed-off-by: Juergen Gross <jgross@suse.com>
Message-ID: <20250407101842.67228-1-roger.pau@citrix.com>
Paolo Bonzini [Tue, 8 Apr 2025 09:49:31 +0000 (05:49 -0400)]
Merge tag 'kvmarm-fixes-6.15-1' of https://git.kernel.org/pub/scm/linux/kernel/git/kvmarm/kvmarm into HEAD
KVM/arm64: First batch of fixes for 6.15
- Rework heuristics for resolving the fault IPA (HPFAR_EL2 v. re-walk
stage-1 page tables) to align with the architecture. This avoids
possibly taking an SEA at EL2 on the page table walk or using an
architecturally UNKNOWN fault IPA.
- Use acquire/release semantics in the KVM FF-A proxy to avoid reading
a stale value for the FF-A version.
- Fix KVM guest driver to match PV CPUID hypercall ABI.
- Use Inner Shareable Normal Write-Back mappings at stage-1 in KVM
selftests, which is the only memory type for which atomic
instructions are architecturally guaranteed to work.
Jakub Kicinski [Fri, 4 Apr 2025 18:03:34 +0000 (11:03 -0700)]
selftests: tls: check that disconnect does nothing
"Inspired" by syzbot test, pre-queue some data, disconnect()
and try to receive(). This used to trigger a warning in TLS's strp.
Now we expect the disconnect() to have almost no effect.
Jakub Kicinski [Fri, 4 Apr 2025 18:03:33 +0000 (11:03 -0700)]
net: tls: explicitly disallow disconnect
syzbot discovered that it can disconnect a TLS socket and then
run into all sort of unexpected corner cases. I have a vague
recollection of Eric pointing this out to us a long time ago.
Supporting disconnect is really hard, for one thing if offload
is enabled we'd need to wait for all packets to be _acked_.
Disconnect is not commonly used, disallow it.
The immediate problem syzbot run into is the warning in the strp,
but that's just the easiest bug to trigger:
sctp: detect and prevent references to a freed transport in sendmsg
sctp_sendmsg() re-uses associations and transports when possible by
doing a lookup based on the socket endpoint and the message destination
address, and then sctp_sendmsg_to_asoc() sets the selected transport in
all the message chunks to be sent.
There's a possible race condition if another thread triggers the removal
of that selected transport, for instance, by explicitly unbinding an
address with setsockopt(SCTP_SOCKOPT_BINDX_REM), after the chunks have
been set up and before the message is sent. This can happen if the send
buffer is full, during the period when the sender thread temporarily
releases the socket lock in sctp_wait_for_sndbuf().
This causes the access to the transport data in
sctp_outq_select_transport(), when the association outqueue is flushed,
to result in a use-after-free read.
This change avoids this scenario by having sctp_transport_free() signal
the freeing of the transport, tagging it as "dead". In order to do this,
the patch restores the "dead" bit in struct sctp_transport, which was
removed in
commit 47faa1e4c50e ("sctp: remove the dead field of sctp_transport").
Then, in the scenario where the sender thread has released the socket
lock in sctp_wait_for_sndbuf(), the bit is checked again after
re-acquiring the socket lock to detect the deletion. This is done while
holding a reference to the transport to prevent it from being freed in
the process.
If the transport was deleted while the socket lock was relinquished,
sctp_sendmsg_to_asoc() will return -EAGAIN to let userspace retry the
send.
The bug was found by a private syzbot instance (see the error report [1]
and the C reproducer that triggers it [2]).
Andy Shevchenko [Wed, 2 Apr 2025 12:20:01 +0000 (15:20 +0300)]
gpiolib: of: Move Atmel HSMCI quirk up out of the regulator comment
The regulator comment in of_gpio_set_polarity_by_property()
made on top of a couple of the cases, while Atmel HSMCI quirk
is not related to that. Make it clear by moving Atmel HSMCI
quirk up out of the scope of the regulator comment.
Andy Shevchenko [Wed, 2 Apr 2025 12:20:00 +0000 (15:20 +0300)]
gpiolib: of: Fix the choice for Ingenic NAND quirk
The Ingenic NAND quirk has been added under CONFIG_LCD_HX8357 ifdeffery
which sounds quite wrong. Fix the choice for Ingenic NAND quirk
by wrapping it into own ifdeffery related to the respective driver.
====================
net_sched: make ->qlen_notify() idempotent
Gerrard reported a vulnerability exists in fq_codel where manipulating
the MTU can cause codel_dequeue() to drop all packets. The parent qdisc's
sch->q.qlen is only updated via ->qlen_notify() if the fq_codel queue
remains non-empty after the drops. This discrepancy in qlen between
fq_codel and its parent can lead to a use-after-free condition.
Let's fix this by making all existing ->qlen_notify() idempotent so that
the sch->q.qlen check will be no longer necessary.
Patch 1~5 make all existing ->qlen_notify() idempotent to prepare for
patch 6 which removes the sch->q.qlen check. They are followed by 5
selftests for each type of Qdisc's we touch here.
All existing and new Qdisc selftests pass after this patchset.
Cong Wang [Thu, 3 Apr 2025 21:16:36 +0000 (14:16 -0700)]
selftests/tc-testing: Add a test case for FQ_CODEL with ETS parent
Add a test case for FQ_CODEL with ETS parent to verify packet drop
behavior when the queue becomes empty. This helps ensure proper
notification mechanisms between qdiscs.
Note this is best-effort, it is hard to play with those parameters
perfectly to always trigger ->qlen_notify().
Cc: Pedro Tammela <pctammela@mojatatu.com> Signed-off-by: Cong Wang <xiyou.wangcong@gmail.com> Reviewed-by: Victor Nogueira <victor@mojatatu.com> Link: https://patch.msgid.link/20250403211636.166257-6-xiyou.wangcong@gmail.com Acked-by: Jamal Hadi Salim <jhs@mojatatu.com> Signed-off-by: Paolo Abeni <pabeni@redhat.com>
Cong Wang [Thu, 3 Apr 2025 21:16:35 +0000 (14:16 -0700)]
selftests/tc-testing: Add a test case for FQ_CODEL with DRR parent
Add a test case for FQ_CODEL with DRR parent to verify packet drop
behavior when the queue becomes empty. This helps ensure proper
notification mechanisms between qdiscs.
Note this is best-effort, it is hard to play with those parameters
perfectly to always trigger ->qlen_notify().
Cc: Pedro Tammela <pctammela@mojatatu.com> Signed-off-by: Cong Wang <xiyou.wangcong@gmail.com> Reviewed-by: Victor Nogueira <victor@mojatatu.com> Link: https://patch.msgid.link/20250403211636.166257-5-xiyou.wangcong@gmail.com Acked-by: Jamal Hadi Salim <jhs@mojatatu.com> Signed-off-by: Paolo Abeni <pabeni@redhat.com>
Cong Wang [Thu, 3 Apr 2025 21:16:34 +0000 (14:16 -0700)]
selftests/tc-testing: Add a test case for FQ_CODEL with HFSC parent
Add a test case for FQ_CODEL with HFSC parent to verify packet drop
behavior when the queue becomes empty. This helps ensure proper
notification mechanisms between qdiscs.
Note this is best-effort, it is hard to play with those parameters
perfectly to always trigger ->qlen_notify().
Cc: Pedro Tammela <pctammela@mojatatu.com> Signed-off-by: Cong Wang <xiyou.wangcong@gmail.com> Reviewed-by: Victor Nogueira <victor@mojatatu.com> Link: https://patch.msgid.link/20250403211636.166257-4-xiyou.wangcong@gmail.com Acked-by: Jamal Hadi Salim <jhs@mojatatu.com> Signed-off-by: Paolo Abeni <pabeni@redhat.com>
Cong Wang [Thu, 3 Apr 2025 21:16:33 +0000 (14:16 -0700)]
selftests/tc-testing: Add a test case for FQ_CODEL with QFQ parent
Add a test case for FQ_CODEL with QFQ parent to verify packet drop
behavior when the queue becomes empty. This helps ensure proper
notification mechanisms between qdiscs.
Note this is best-effort, it is hard to play with those parameters
perfectly to always trigger ->qlen_notify().
Cc: Pedro Tammela <pctammela@mojatatu.com> Signed-off-by: Cong Wang <xiyou.wangcong@gmail.com> Reviewed-by: Victor Nogueira <victor@mojatatu.com> Link: https://patch.msgid.link/20250403211636.166257-3-xiyou.wangcong@gmail.com Acked-by: Jamal Hadi Salim <jhs@mojatatu.com> Signed-off-by: Paolo Abeni <pabeni@redhat.com>
Cong Wang [Thu, 3 Apr 2025 21:16:32 +0000 (14:16 -0700)]
selftests/tc-testing: Add a test case for FQ_CODEL with HTB parent
Add a test case for FQ_CODEL with HTB parent to verify packet drop
behavior when the queue becomes empty. This helps ensure proper
notification mechanisms between qdiscs.
Note this is best-effort, it is hard to play with those parameters
perfectly to always trigger ->qlen_notify().
Cc: Pedro Tammela <pctammela@mojatatu.com> Signed-off-by: Cong Wang <xiyou.wangcong@gmail.com> Reviewed-by: Victor Nogueira <victor@mojatatu.com> Link: https://patch.msgid.link/20250403211636.166257-2-xiyou.wangcong@gmail.com Acked-by: Jamal Hadi Salim <jhs@mojatatu.com> Signed-off-by: Paolo Abeni <pabeni@redhat.com>
Cong Wang [Thu, 3 Apr 2025 21:16:31 +0000 (14:16 -0700)]
codel: remove sch->q.qlen check before qdisc_tree_reduce_backlog()
After making all ->qlen_notify() callbacks idempotent, now it is safe to
remove the check of qlen!=0 from both fq_codel_dequeue() and
codel_qdisc_dequeue().
Reported-by: Gerrard Tai <gerrard.tai@starlabs.sg> Fixes: 4b549a2ef4be ("fq_codel: Fair Queue Codel AQM") Fixes: 76e3cc126bb2 ("codel: Controlled Delay AQM") Signed-off-by: Cong Wang <xiyou.wangcong@gmail.com> Reviewed-by: Simon Horman <horms@kernel.org> Link: https://patch.msgid.link/20250403211636.166257-1-xiyou.wangcong@gmail.com Acked-by: Jamal Hadi Salim <jhs@mojatatu.com> Signed-off-by: Paolo Abeni <pabeni@redhat.com>
Cong Wang [Thu, 3 Apr 2025 21:10:27 +0000 (14:10 -0700)]
sch_ets: make est_qlen_notify() idempotent
est_qlen_notify() deletes its class from its active list with
list_del() when qlen is 0, therefore, it is not idempotent and
not friendly to its callers, like fq_codel_dequeue().
Let's make it idempotent to ease qdisc_tree_reduce_backlog() callers'
life. Also change other list_del()'s to list_del_init() just to be
extra safe.
Cong Wang [Thu, 3 Apr 2025 21:10:26 +0000 (14:10 -0700)]
sch_qfq: make qfq_qlen_notify() idempotent
qfq_qlen_notify() always deletes its class from its active list
with list_del_init() _and_ calls qfq_deactivate_agg() when the whole list
becomes empty.
To make it idempotent, just skip everything when it is not in the active
list.
Also change other list_del()'s to list_del_init() just to be extra safe.
Reported-by: Gerrard Tai <gerrard.tai@starlabs.sg> Signed-off-by: Cong Wang <xiyou.wangcong@gmail.com> Reviewed-by: Simon Horman <horms@kernel.org> Link: https://patch.msgid.link/20250403211033.166059-5-xiyou.wangcong@gmail.com Acked-by: Jamal Hadi Salim <jhs@mojatatu.com> Signed-off-by: Paolo Abeni <pabeni@redhat.com>
Cong Wang [Thu, 3 Apr 2025 21:10:25 +0000 (14:10 -0700)]
sch_hfsc: make hfsc_qlen_notify() idempotent
hfsc_qlen_notify() is not idempotent either and not friendly
to its callers, like fq_codel_dequeue(). Let's make it idempotent
to ease qdisc_tree_reduce_backlog() callers' life:
1. update_vf() decreases cl->cl_nactive, so we can check whether it is
non-zero before calling it.
2. eltree_remove() always removes RB node cl->el_node, but we can use
RB_EMPTY_NODE() + RB_CLEAR_NODE() to make it safe.
Reported-by: Gerrard Tai <gerrard.tai@starlabs.sg> Signed-off-by: Cong Wang <xiyou.wangcong@gmail.com> Reviewed-by: Simon Horman <horms@kernel.org> Link: https://patch.msgid.link/20250403211033.166059-4-xiyou.wangcong@gmail.com Acked-by: Jamal Hadi Salim <jhs@mojatatu.com> Signed-off-by: Paolo Abeni <pabeni@redhat.com>
Cong Wang [Thu, 3 Apr 2025 21:10:24 +0000 (14:10 -0700)]
sch_drr: make drr_qlen_notify() idempotent
drr_qlen_notify() always deletes the DRR class from its active list
with list_del(), therefore, it is not idempotent and not friendly
to its callers, like fq_codel_dequeue().
Let's make it idempotent to ease qdisc_tree_reduce_backlog() callers'
life. Also change other list_del()'s to list_del_init() just to be
extra safe.
Reported-by: Gerrard Tai <gerrard.tai@starlabs.sg> Signed-off-by: Cong Wang <xiyou.wangcong@gmail.com> Reviewed-by: Simon Horman <horms@kernel.org> Link: https://patch.msgid.link/20250403211033.166059-3-xiyou.wangcong@gmail.com Acked-by: Jamal Hadi Salim <jhs@mojatatu.com> Signed-off-by: Paolo Abeni <pabeni@redhat.com>
Cong Wang [Thu, 3 Apr 2025 21:10:23 +0000 (14:10 -0700)]
sch_htb: make htb_qlen_notify() idempotent
htb_qlen_notify() always deactivates the HTB class and in fact could
trigger a warning if it is already deactivated. Therefore, it is not
idempotent and not friendly to its callers, like fq_codel_dequeue().
Let's make it idempotent to ease qdisc_tree_reduce_backlog() callers'
life.
Reported-by: Gerrard Tai <gerrard.tai@starlabs.sg> Signed-off-by: Cong Wang <xiyou.wangcong@gmail.com> Reviewed-by: Simon Horman <horms@kernel.org> Link: https://patch.msgid.link/20250403211033.166059-2-xiyou.wangcong@gmail.com Acked-by: Jamal Hadi Salim <jhs@mojatatu.com> Signed-off-by: Paolo Abeni <pabeni@redhat.com>
gpio: TODO: track the removal of regulator-related workarounds
The GPIOD_FLAGS_BIT_NONEXCLUSIVE flag and devm_gpiod_unhinge() function
should be replaced with a better solution. The pwrseq subsystem is a good
candidate. GPIOs themselves should remain a unique resource. Add a task
for tracking the removal of these deprecated symbols.
MAINTAINERS: add more keywords for the GPIO subsystem entry
Add GPIOD_FLAGS_BIT_NONEXCLUSIVE and devm_gpiod_unhinge as keywords to
the GPIO entry so that we get notified if anybody tries to use these
deprecated symbols. We'll drop them from here once we remove them from
the kernel.
This function was introduced as a workaround for an issue with resource
ownership in the regulator subsystem. Rather than passing the ownership
of a GPIO, we should make the regulator core be able to deal with
resources it didn't request. Deprecate this function so that we don't
get more users in the tree.
gpio: deprecate the GPIOD_FLAGS_BIT_NONEXCLUSIVE flag
The non-exclusive GPIO request flag looks like a functional feature but
is in fact a workaround for a corner-case that got out of hand. It should
be removed so deprecate it officially so that nobody uses it anymore.
In case the backlog transmit queue for system-importance messages is overloaded,
tipc_link_xmit() returns -ENOBUFS but the skb list is not purged. This leads to
memory leak and failure when a skb is allocated.
This commit fixes this issue by purging the skb list before tipc_link_xmit()
returns.
Objtool uses an arbitrary rule for INSN_SYSCALL and INSN_SYSRET that
almost works by accident: if it's in a function, control flow continues
after the instruction, otherwise it terminates.
That behavior should instead be based on the semantics of the underlying
instruction. Change INSN_SYSCALL to always preserve control flow and
INSN_SYSRET to always terminate it.
The changed semantic for INSN_SYSCALL requires a tweak to the
!CONFIG_IA32_EMULATION version of xen_entry_SYSCALL_compat(). In Xen,
SYSCALL is a hypercall which usually returns. But in this case it's a
hypercall to IRET which doesn't return. Add UD2 to tell objtool to
terminate control flow, and to prevent undefined behavior at runtime.
projects / nvme.git / log