Linux kernel
============
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several of them using the Restructured Text markup notation.
Please read the Documentation/process/changes.rst file, as it contains the
requirements for building and running the kernel, and information about
the problems which may result by upgrading your kernel.
code
Clone this repository
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Pull irq fix from Borislav Petkov:
- Cleanup the firmware node for the new IRQ MSI domain properly, to
avoid leaking memory
* tag 'irq_urgent_for_v6.2_rc6' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip:
genirq/msi: Free the fwnode created by msi_create_device_irq_domain()
Pull x86 fixes from Borislav Petkov:
- Start checking for -mindirect-branch-cs-prefix clang support too now
that LLVM 16 will support it
- Fix a NULL ptr deref when suspending with Xen PV
- Have a SEV-SNP guest check explicitly for features enabled by the
hypervisor and fail gracefully if some are unsupported by the guest
instead of failing in a non-obvious and hard-to-debug way
- Fix a MSI descriptor leakage under Xen
- Mark Xen's MSI domain as supporting MSI-X
- Prevent legacy PIC interrupts from being resent in software by
marking them level triggered, as they should be, which lead to a NULL
ptr deref
* tag 'x86_urgent_for_v6.2_rc6' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip:
x86/build: Move '-mindirect-branch-cs-prefix' out of GCC-only block
acpi: Fix suspend with Xen PV
x86/sev: Add SEV-SNP guest feature negotiation support
x86/pci/xen: Fixup fallout from the PCI/MSI overhaul
x86/pci/xen: Set MSI_FLAG_PCI_MSIX support in Xen MSI domain
x86/i8259: Mark legacy PIC interrupts with IRQ_LEVEL
msi_create_device_irq_domain() creates a firmware node for the new domain,
which is never freed. kmemleak reports:
unreferenced object 0xffff888120ba9a00 (size 96):
comm "systemd-modules", pid 221, jiffies 4294893411 (age 635.732s)
hex dump (first 32 bytes):
00 00 00 00 00 00 00 00 e0 19 8b 83 ff ff ff ff ................
00 00 00 00 00 00 00 00 18 9a ba 20 81 88 ff ff ........... ....
backtrace:
[<000000008cdbc98d>] __irq_domain_alloc_fwnode+0x51/0x2b0
[<00000000c57acf9d>] msi_create_device_irq_domain+0x283/0x670
[<000000009b567982>] __pci_enable_msix_range+0x49e/0xdb0
[<0000000077cc1445>] pci_alloc_irq_vectors_affinity+0x11f/0x1c0
[<00000000532e9ef5>] mlx5_irq_table_create+0x24c/0x940 [mlx5_core]
[<00000000fabd2b80>] mlx5_load+0x1fa/0x680 [mlx5_core]
[<000000006bb22ae4>] mlx5_init_one+0x485/0x670 [mlx5_core]
[<00000000eaa5e1ad>] probe_one+0x4c2/0x720 [mlx5_core]
[<00000000df8efb43>] local_pci_probe+0xd6/0x170
[<0000000085cb9924>] pci_device_probe+0x231/0x6e0
Use the proper free operation for the firmware wnode so the name is freed
during error unwind of msi_create_device_irq_domain() and also free the
node in msi_remove_device_irq_domain() if it was automatically allocated.
To avoid extra NULL pointer checks make irq_domain_free_fwnode() tolerant
of NULL.
Fixes: 27a6dea3ebaa ("genirq/msi: Provide msi_create/free_device_irq_domain()")
Reported-by: Omri Barazi <obarazi@nvidia.com>
Signed-off-by: Jason Gunthorpe <jgg@nvidia.com>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Tested-by: Kalle Valo <kvalo@kernel.org>
Tested-by: Leon Romanovsky <leonro@nvidia.com>
Link: https://lore.kernel.org/r/0-v2-24af6665e2da+c9-msi_leak_jgg@nvidia.com
Pull input fixes from Dmitry Torokhov:
- touchpads on HP 15-* laptops switched back to PS/2 emulation mode
- a quirk for Clevo PCX0DX/TUXEDO XP1511 to make sure keyboard is
responding after resume
* tag 'input-for-v6.2-rc5' of git://git.kernel.org/pub/scm/linux/kernel/git/dtor/input:
Input: i8042 - add Clevo PCX0DX to i8042 quirk table
Revert "Input: synaptics - switch touchpad on HP Laptop 15-da3001TU to RMI mode"
LLVM 16 will have support for this flag so move it out of the GCC-only
block to allow LLVM builds to take advantage of it.
Signed-off-by: Nathan Chancellor <nathan@kernel.org>
Signed-off-by: Ingo Molnar <mingo@kernel.org>
Tested-by: Nick Desaulniers <ndesaulniers@google.com>
Reviewed-by: Nick Desaulniers <ndesaulniers@google.com>
Acked-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Link: https://github.com/ClangBuiltLinux/linux/issues/1665
Link: https://github.com/llvm/llvm-project/commit/6f867f9102838ebe314c1f3661fdf95700386e5a
Link: https://lore.kernel.org/r/20230120165826.2469302-1-nathan@kernel.org
Pull cxl fixes from Dan Williams:
"A couple of fixes for bugs introduced during the merge window. One is
a regression, the other was a bug in the CXL AER handler:
- Fix a crash regression due to module load order of cxl_pmem.ko
- Fix wrong register offset read in CXL AER handling path"
* tag 'cxl-fixes-for-6.2-rc6' of git://git.kernel.org/pub/scm/linux/kernel/git/cxl/cxl:
cxl/pmem: Fix nvdimm unregistration when cxl_pmem driver is absent
cxl: fix cxl_report_and_clear() RAS UE addr mis-assignment
The Clevo PCX0DX/TUXEDO XP1511, need quirks for the keyboard to not be
occasionally unresponsive after resume.
Signed-off-by: Werner Sembach <wse@tuxedocomputers.com>
Cc: stable@vger.kernel.org
Reviewed-by: Hans de Goede <hdegoede@redhat.com>
Reviewed-by: Mattijs Korpershoek <mkorpershoek@baylibre.com>
Link: https://lore.kernel.org/r/20230110134524.553620-1-wse@tuxedocomputers.com
Signed-off-by: Dmitry Torokhov <dmitry.torokhov@gmail.com>
Commit f1e525009493 ("x86/boot: Skip realmode init code when running as
Xen PV guest") missed one code path accessing real_mode_header, leading
to dereferencing NULL when suspending the system under Xen:
[ 348.284004] PM: suspend entry (deep)
[ 348.289532] Filesystems sync: 0.005 seconds
[ 348.291545] Freezing user space processes ... (elapsed 0.000 seconds) done.
[ 348.292457] OOM killer disabled.
[ 348.292462] Freezing remaining freezable tasks ... (elapsed 0.104 seconds) done.
[ 348.396612] printk: Suspending console(s) (use no_console_suspend to debug)
[ 348.749228] PM: suspend devices took 0.352 seconds
[ 348.769713] ACPI: EC: interrupt blocked
[ 348.816077] BUG: kernel NULL pointer dereference, address: 000000000000001c
[ 348.816080] #PF: supervisor read access in kernel mode
[ 348.816081] #PF: error_code(0x0000) - not-present page
[ 348.816083] PGD 0 P4D 0
[ 348.816086] Oops: 0000 [#1] PREEMPT SMP NOPTI
[ 348.816089] CPU: 0 PID: 6764 Comm: systemd-sleep Not tainted 6.1.3-1.fc32.qubes.x86_64 #1
[ 348.816092] Hardware name: Star Labs StarBook/StarBook, BIOS 8.01 07/03/2022
[ 348.816093] RIP: e030:acpi_get_wakeup_address+0xc/0x20
Fix that by adding an optional acpi callback allowing to skip setting
the wakeup address, as in the Xen PV case this will be handled by the
hypervisor anyway.
Fixes: f1e525009493 ("x86/boot: Skip realmode init code when running as Xen PV guest")
Reported-by: Marek Marczykowski-Górecki <marmarek@invisiblethingslab.com>
Signed-off-by: Juergen Gross <jgross@suse.com>
Signed-off-by: Dave Hansen <dave.hansen@linux.intel.com>
Acked-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
Link: https://lore.kernel.org/all/20230117155724.22940-1-jgross%40suse.com
Pull x86 fixes from Borislav Petkov:
- Make sure the poking PGD is pinned for Xen PV as it requires it this
way
- Fixes for two resctrl races when moving a task or creating a new
monitoring group
- Fix SEV-SNP guests running under HyperV where MTRRs are disabled to
not return a UC- type mapping type on memremap() and thus cause a
serious slowdown
- Fix insn mnemonics in bioscall.S now that binutils is starting to fix
confusing insn suffixes
* tag 'x86_urgent_for_v6.2_rc4' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip:
x86/mm: fix poking_init() for Xen PV guests
x86/resctrl: Fix event counts regression in reused RMIDs
x86/resctrl: Fix task CLOSID/RMID update race
x86/pat: Fix pat_x_mtrr_type() for MTRR disabled case
x86/boot: Avoid using Intel mnemonics in AT&T syntax asm
This reverts commit 7efc3b7261030da79001c00d92bc3392fd6c664c.
We have got openSUSE reports (Link 1) for 6.1 kernel with khugepaged
stalling CPU for long periods of time. Investigation of tracepoint data
shows that compaction is stuck in repeating fast_find_migrateblock()
based migrate page isolation, and then fails to migrate all isolated
pages.
Commit 7efc3b726103 ("mm/compaction: fix set skip in fast_find_migrateblock")
was suspected as it was merged in 6.1 and in theory can indeed remove a
termination condition for fast_find_migrateblock() under certain
conditions, as it removes a place that always marks a scanned pageblock
from being re-scanned. There are other such places, but those can be
skipped under certain conditions, which seems to match the tracepoint
data.
Testing of revert also appears to have resolved the issue, thus revert
the commit until a more robust solution for the original problem is
developed.
It's also likely this will fix qemu stalls with 6.1 kernel reported in
Link 2, but that is not yet confirmed.
Link: https://bugzilla.suse.com/show_bug.cgi?id=1206848
Link: https://lore.kernel.org/kvm/b8017e09-f336-3035-8344-c549086c2340@kernel.org/
Link: https://lore.kernel.org/lkml/20230125134434.18017-1-mgorman@techsingularity.net/
Fixes: 7efc3b726103 ("mm/compaction: fix set skip in fast_find_migrateblock")
Cc: <stable@vger.kernel.org>
Tested-by: Pedro Falcato <pedro.falcato@gmail.com>
Acked-by: Mel Gorman <mgorman@techsingularity.net>
Signed-off-by: Vlastimil Babka <vbabka@suse.cz>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
The cxl_pmem.ko module houses the driver for both cxl_nvdimm_bridge
objects and cxl_nvdimm objects. When the core creates a cxl_nvdimm it
arranges for it to be autoremoved when the bridge goes down. However, if
the bridge never initialized because the cxl_pmem.ko module never
loaded, it sets up a the following crash scenario:
BUG: kernel NULL pointer dereference, address: 0000000000000478
[..]
RIP: 0010:cxl_nvdimm_probe+0x99/0x140 [cxl_pmem]
[..]
Call Trace:
<TASK>
cxl_bus_probe+0x17/0x50 [cxl_core]
really_probe+0xde/0x380
__driver_probe_device+0x78/0x170
driver_probe_device+0x1f/0x90
__driver_attach+0xd2/0x1c0
bus_for_each_dev+0x79/0xc0
bus_add_driver+0x1b1/0x200
driver_register+0x89/0xe0
cxl_pmem_init+0x50/0xff0 [cxl_pmem]
It turns out the recent rework to simplify nvdimm probing obviated the
need to unregister cxl_nvdimm objects at cxl_nvdimm_bridge ->remove()
time. Leave the cxl_nvdimm device registered until the hosting
cxl_memdev departs. The alternative is that the cxl_memdev needs to be
reattached whenever the cxl_nvdimm_bridge attach state cycles, which is
awkward and unnecessary.
The only requirement is to make sure that when the cxl_nvdimm_bridge
goes away any dependent cxl_nvdimm objects are shutdown. Handle that in
unregister_nvdimm_bus().
With these registration entanglements removed there is no longer a need
to pre-load the cxl_pmem module in cxl_acpi.
Fixes: cb9cfff82f6a ("cxl/acpi: Simplify cxl_nvdimm_bridge probing")
Reported-by: Gregory Price <gregory.price@memverge.com>
Debugged-by: Jonathan Cameron <Jonathan.Cameron@huawei.com>
Tested-by: Jonathan Cameron <Jonathan.Cameron@huawei.com>
Reviewed-by: Jonathan Cameron <Jonathan.Cameron@huawei.com>
Reviewed-by: Dave Jiang <dave.jiang@intel.com>
Link: https://lore.kernel.org/r/167426077263.3955046.9695309346988027311.stgit@dwillia2-xfh.jf.intel.com
Signed-off-by: Dan Williams <dan.j.williams@intel.com>
This reverts commit ac5408991ea6b06e29129b4d4861097c4c3e0d59 because
it causes loss of keyboard on HP 15-da1xxx.
Fixes: ac5408991ea6 ("Input: synaptics - switch touchpad on HP Laptop 15-da3001TU to RMI mode")
Reported-by: Jiri Slaby <jirislaby@kernel.org>
Link: https://lore.kernel.org/r/824effa5-8b9a-c28a-82bb-9b0ab24623e1@kernel.org
Bugzilla: https://bugzilla.suse.com/show_bug.cgi?id=1206358
Cc: stable@vger.kernel.org
Signed-off-by: Dmitry Torokhov <dmitry.torokhov@gmail.com>
The hypervisor can enable various new features (SEV_FEATURES[1:63]) and start a
SNP guest. Some of these features need guest side implementation. If any of
these features are enabled without it, the behavior of the SNP guest will be
undefined. It may fail booting in a non-obvious way making it difficult to
debug.
Instead of allowing the guest to continue and have it fail randomly later,
detect this early and fail gracefully.
The SEV_STATUS MSR indicates features which the hypervisor has enabled. While
booting, SNP guests should ascertain that all the enabled features have guest
side implementation. In case a feature is not implemented in the guest, the
guest terminates booting with GHCB protocol Non-Automatic Exit(NAE) termination
request event, see "SEV-ES Guest-Hypervisor Communication Block Standardization"
document (currently at https://developer.amd.com/wp-content/resources/56421.pdf),
section "Termination Request".
Populate SW_EXITINFO2 with mask of unsupported features that the hypervisor can
easily report to the user.
More details in the AMD64 APM Vol 2, Section "SEV_STATUS MSR".
[ bp:
- Massage.
- Move snp_check_features() call to C code.
Note: the CC:stable@ aspect here is to be able to protect older, stable
kernels when running on newer hypervisors. Or not "running" but fail
reliably and in a well-defined manner instead of randomly. ]
Fixes: cbd3d4f7c4e5 ("x86/sev: Check SEV-SNP features support")
Signed-off-by: Nikunj A Dadhania <nikunj@amd.com>
Signed-off-by: Borislav Petkov (AMD) <bp@alien8.de>
Reviewed-by: Tom Lendacky <thomas.lendacky@amd.com>
Cc: <stable@kernel.org>
Link: https://lore.kernel.org/r/20230118061943.534309-1-nikunj@amd.com
Pull EDAC fixes from Borislav Petkov:
- Fix the EDAC device's confusion in the polling setting units
- Fix a memory leak in highbank's probing function
* tag 'edac_urgent_for_v6.2_rc4' of git://git.kernel.org/pub/scm/linux/kernel/git/ras/ras:
EDAC/highbank: Fix memory leak in highbank_mc_probe()
EDAC/device: Fix period calculation in edac_device_reset_delay_period()