- 24 Nov, 2021 28 commits
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Nicholas Piggin authored
This juggles SPR switching on the entry and exit sides to be more symmetric, which makes the next refactoring patch possible with no functional change. Signed-off-by: Nicholas Piggin <npiggin@gmail.com> Signed-off-by: Michael Ellerman <mpe@ellerman.id.au> Link: https://lore.kernel.org/r/20211123095231.1036501-28-npiggin@gmail.com
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Nicholas Piggin authored
Keep better track of the current SPR value in places where they are to be loaded with a new context, to reduce expensive mtSPR operations. Signed-off-by: Nicholas Piggin <npiggin@gmail.com> Signed-off-by: Michael Ellerman <mpe@ellerman.id.au> Link: https://lore.kernel.org/r/20211123095231.1036501-27-npiggin@gmail.com
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Nicholas Piggin authored
Avoid interleaving mfSPR and mtSPR to reduce SPR scoreboard stalls. Signed-off-by: Nicholas Piggin <npiggin@gmail.com> Signed-off-by: Michael Ellerman <mpe@ellerman.id.au> Link: https://lore.kernel.org/r/20211123095231.1036501-26-npiggin@gmail.com
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Nicholas Piggin authored
Reduce the number of mfTB executed by passing the current timebase around entry and exit code rather than read it multiple times. Signed-off-by: Nicholas Piggin <npiggin@gmail.com> Signed-off-by: Michael Ellerman <mpe@ellerman.id.au> Link: https://lore.kernel.org/r/20211123095231.1036501-25-npiggin@gmail.com
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Nicholas Piggin authored
Move the TB updates between saving and loading guest and host SPRs, to improve scheduling by keeping issue-NTC operations together as much as possible. Signed-off-by: Nicholas Piggin <npiggin@gmail.com> Signed-off-by: Michael Ellerman <mpe@ellerman.id.au> Link: https://lore.kernel.org/r/20211123095231.1036501-24-npiggin@gmail.com
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Nicholas Piggin authored
Change dec_expires to be relative to the guest timebase, and allow it to be moved into low level P9 guest entry functions, to improve SPR access scheduling. Signed-off-by: Nicholas Piggin <npiggin@gmail.com> Signed-off-by: Michael Ellerman <mpe@ellerman.id.au> Link: https://lore.kernel.org/r/20211123095231.1036501-23-npiggin@gmail.com
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Nicholas Piggin authored
Small cleanup makes it a bit easier to match up entry and exit operations. Signed-off-by: Nicholas Piggin <npiggin@gmail.com> Reviewed-by: Fabiano Rosas <farosas@linux.ibm.com> Signed-off-by: Michael Ellerman <mpe@ellerman.id.au> Link: https://lore.kernel.org/r/20211123095231.1036501-22-npiggin@gmail.com
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Nicholas Piggin authored
Moving the mtmsrd after the host SPRs are saved and before the guest SPRs start to be loaded can prevent an SPR scoreboard stall (because the mtmsrd is L=1 type which does not cause context synchronisation. This is also now more convenient to combined with the mtmsrd L=0 instruction to enable facilities just below, but that is not done yet. Signed-off-by: Nicholas Piggin <npiggin@gmail.com> Signed-off-by: Michael Ellerman <mpe@ellerman.id.au> Link: https://lore.kernel.org/r/20211123095231.1036501-21-npiggin@gmail.com
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Nicholas Piggin authored
This reduces the number of mtmsrd required to enable facility bits when saving/restoring registers, by having the KVM code set all bits up front rather than using individual facility functions that set their particular MSR bits. Signed-off-by: Nicholas Piggin <npiggin@gmail.com> Reviewed-by: Fabiano Rosas <farosas@linux.ibm.com> Signed-off-by: Michael Ellerman <mpe@ellerman.id.au> Link: https://lore.kernel.org/r/20211123095231.1036501-20-npiggin@gmail.com
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Nicholas Piggin authored
Move the SPR update into its relevant helper function. This will help with SPR scheduling improvements in later changes. Signed-off-by: Nicholas Piggin <npiggin@gmail.com> Reviewed-by: Fabiano Rosas <farosas@linux.ibm.com> Signed-off-by: Michael Ellerman <mpe@ellerman.id.au> Link: https://lore.kernel.org/r/20211123095231.1036501-19-npiggin@gmail.com
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Nicholas Piggin authored
Processors that support KVM HV do not require read-modify-write of the CTRL SPR to set/clear their thread's runlatch. Just write 1 or 0 to it. Signed-off-by: Nicholas Piggin <npiggin@gmail.com> Reviewed-by: Fabiano Rosas <farosas@linux.ibm.com> Signed-off-by: Michael Ellerman <mpe@ellerman.id.au> Link: https://lore.kernel.org/r/20211123095231.1036501-18-npiggin@gmail.com
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Nicholas Piggin authored
Factor duplicated code into a helper function. Signed-off-by: Nicholas Piggin <npiggin@gmail.com> Reviewed-by: Fabiano Rosas <farosas@linux.ibm.com> Signed-off-by: Michael Ellerman <mpe@ellerman.id.au> Link: https://lore.kernel.org/r/20211123095231.1036501-17-npiggin@gmail.com
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Nicholas Piggin authored
The pmcregs_in_use field in the guest VPA can not be trusted to reflect what the guest is doing with PMU SPRs, so the PMU must always be managed (stopped) when exiting the guest, and SPR values set when entering the guest to ensure it can't cause a covert channel or otherwise cause other guests or the host to misbehave. So prevent guest access to the PMU with HFSCR[PM] if pmcregs_in_use is clear, and avoid the PMU SPR access on every partition switch. Guests that set pmcregs_in_use incorrectly or when first setting it and using the PMU will take a hypervisor facility unavailable interrupt that will bring in the PMU SPRs. Signed-off-by: Nicholas Piggin <npiggin@gmail.com> Reviewed-by: Athira Jajeev <atrajeev@linux.vnet.ibm.com> Signed-off-by: Michael Ellerman <mpe@ellerman.id.au> Link: https://lore.kernel.org/r/20211123095231.1036501-16-npiggin@gmail.com
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Nicholas Piggin authored
Rather than guest/host save/retsore functions, implement context switch functions that take care of details like the VPA update for nested. The reason to split these kind of helpers into explicit save/load functions is mainly to schedule SPR access nicely, but PMU is a special case where the load requires mtSPR (to stop counters) and other difficulties, so there's less possibility to schedule those nicely. The SPR accesses also have side-effects if the PMU is running, and in later changes we keep the host PMU running as long as possible so this code can be better profiled, which also complicates scheduling. Signed-off-by: Nicholas Piggin <npiggin@gmail.com> Reviewed-by: Athira Jajeev <atrajeev@linux.vnet.ibm.com> Signed-off-by: Michael Ellerman <mpe@ellerman.id.au> Link: https://lore.kernel.org/r/20211123095231.1036501-15-npiggin@gmail.com
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Nicholas Piggin authored
Implement the P9 path PMU save/restore code in C, and remove the POWER9/10 code from the P7/8 path assembly. Signed-off-by: Nicholas Piggin <npiggin@gmail.com> Reviewed-by: Athira Jajeev <atrajeev@linux.vnet.ibm.com> Signed-off-by: Michael Ellerman <mpe@ellerman.id.au> Link: https://lore.kernel.org/r/20211123095231.1036501-14-npiggin@gmail.com
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Nicholas Piggin authored
It can be useful in simulators (with very constrained environments) to allow some PMCs to run from boot so they can be sampled directly by a test harness, rather than having to run perf. A previous change freezes counters at boot by default, so provide a boot time option to un-freeze (plus a bit more flexibility). Signed-off-by: Nicholas Piggin <npiggin@gmail.com> Reviewed-by: Athira Jajeev <atrajeev@linux.vnet.ibm.com> Signed-off-by: Michael Ellerman <mpe@ellerman.id.au> Link: https://lore.kernel.org/r/20211123095231.1036501-13-npiggin@gmail.com
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Nicholas Piggin authored
KVM PMU management code looks for particular frozen/disabled bits in the PMU registers so it knows whether it must clear them when coming out of a guest or not. Setting this up helps KVM make these optimisations without getting confused. Longer term the better approach might be to move guest/host PMU switching to the perf subsystem. Signed-off-by: Nicholas Piggin <npiggin@gmail.com> Reviewed-by: Athira Jajeev <atrajeev@linux.vnet.ibm.com> Signed-off-by: Michael Ellerman <mpe@ellerman.id.au> Link: https://lore.kernel.org/r/20211123095231.1036501-12-npiggin@gmail.com
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Nicholas Piggin authored
Provide a config option that controls the workaround added by commit 63279eeb ("KVM: PPC: Book3S HV: Always save guest pmu for guest capable of nesting"). The option defaults to y for now, but is expected to go away within a few releases. Nested capable guests running with the earlier commit 17826638 ("KVM: PPC: Book3S HV Nested: Reflect guest PMU in-use to L0 when guest SPRs are live") will now indicate the PMU in-use status of their guests, which means the parent does not need to unconditionally save the PMU for nested capable guests. After this latest round of performance optimisations, this option costs about 540 cycles or 10% entry/exit performance on a POWER9 nested-capable guest. Signed-off-by: Nicholas Piggin <npiggin@gmail.com> Reviewed-by: Fabiano Rosas <farosas@linux.ibm.com> References: 17826638 ("KVM: PPC: Book3S HV Nested: Reflect guest PMU in-use to L0 when guest SPRs are live") Signed-off-by: Michael Ellerman <mpe@ellerman.id.au> Link: https://lore.kernel.org/r/20211123095231.1036501-11-npiggin@gmail.com
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Nicholas Piggin authored
This register controls supervisor SPR modifications, and as such is only relevant for KVM. KVM always sets AMOR to ~0 on guest entry, and never restores it coming back out to the host, so it can be kept constant and avoid the mtSPR in KVM guest entry. Signed-off-by: Nicholas Piggin <npiggin@gmail.com> Reviewed-by: Fabiano Rosas <farosas@linux.ibm.com> Signed-off-by: Michael Ellerman <mpe@ellerman.id.au> Link: https://lore.kernel.org/r/20211123095231.1036501-10-npiggin@gmail.com
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Nicholas Piggin authored
HV interrupts may be taken with the MMU enabled when radix guests are running. Enable LPCR[HAIL] on ISA v3.1 processors for radix guests. Make this depend on the host LPCR[HAIL] being enabled. Currently that is always enabled, but having this test means any issue that might require LPCR[HAIL] to be disabled in the host will not have to be duplicated in KVM. This optimisation takes 1380 cycles off a NULL hcall entry+exit micro benchmark on a POWER10. Signed-off-by: Nicholas Piggin <npiggin@gmail.com> Reviewed-by: Fabiano Rosas <farosas@linux.ibm.com> Signed-off-by: Michael Ellerman <mpe@ellerman.id.au> Link: https://lore.kernel.org/r/20211123095231.1036501-9-npiggin@gmail.com
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Nicholas Piggin authored
Rather than have KVM look up the host timer and fiddle with the irq-work internal details, have the powerpc/time.c code provide a function for KVM to re-arm the Linux timer code when exiting a guest. This is implementation has an improvement over existing code of marking a decrementer interrupt as soft-pending if a timer has expired, rather than setting DEC to a -ve value, which tended to cause host timers to take two interrupts (first hdec to exit the guest, then the immediate dec). Signed-off-by: Nicholas Piggin <npiggin@gmail.com> Signed-off-by: Michael Ellerman <mpe@ellerman.id.au> Link: https://lore.kernel.org/r/20211123095231.1036501-8-npiggin@gmail.com
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Nicholas Piggin authored
mftb is serialising (dispatch next-to-complete) so it is heavy weight for a mfspr. Avoid reading it multiple times in the entry or exit paths. A small number of cycles delay to timers is tolerable. Signed-off-by: Nicholas Piggin <npiggin@gmail.com> Reviewed-by: Fabiano Rosas <farosas@linux.ibm.com> Signed-off-by: Michael Ellerman <mpe@ellerman.id.au> Link: https://lore.kernel.org/r/20211123095231.1036501-7-npiggin@gmail.com
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Nicholas Piggin authored
On processors that don't suppress the HDEC exceptions when LPCR[HDICE]=0, this could help reduce needless guest exits due to leftover exceptions on entering the guest. Signed-off-by: Nicholas Piggin <npiggin@gmail.com> Reviewed-by: Alexey Kardashevskiy <aik@ozlabs.ru> Signed-off-by: Michael Ellerman <mpe@ellerman.id.au> Link: https://lore.kernel.org/r/20211123095231.1036501-6-npiggin@gmail.com
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Nicholas Piggin authored
There is no need to save away the host DEC value, as it is derived from the host timer subsystem which maintains the next timer time, so it can be restored from there. Signed-off-by: Nicholas Piggin <npiggin@gmail.com> Signed-off-by: Michael Ellerman <mpe@ellerman.id.au> Link: https://lore.kernel.org/r/20211123095231.1036501-5-npiggin@gmail.com
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Nicholas Piggin authored
The host Linux timer code arms the decrementer with the value 'decrementers_next_tb - current_tb' using set_dec(), which stores val - 1 on Book3S-64, which is not quite the same as what KVM does to re-arm the host decrementer when exiting the guest. This shouldn't be a significant change, but it makes the logic match and avoids this small extra change being brought into the next patch. Suggested-by: Alexey Kardashevskiy <aik@ozlabs.ru> Signed-off-by: Nicholas Piggin <npiggin@gmail.com> Signed-off-by: Michael Ellerman <mpe@ellerman.id.au> Link: https://lore.kernel.org/r/20211123095231.1036501-4-npiggin@gmail.com
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Nicholas Piggin authored
The TIDR SPR only exists on POWER9. Avoid accessing it when the feature bit for it is not set. Signed-off-by: Nicholas Piggin <npiggin@gmail.com> Reviewed-by: Fabiano Rosas <farosas@linux.ibm.com> Signed-off-by: Michael Ellerman <mpe@ellerman.id.au> Link: https://lore.kernel.org/r/20211123095231.1036501-3-npiggin@gmail.com
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Nicholas Piggin authored
This removes a missed remnant of the WORT SPR. Signed-off-by: Nicholas Piggin <npiggin@gmail.com> Signed-off-by: Michael Ellerman <mpe@ellerman.id.au> Link: https://lore.kernel.org/r/20211123095231.1036501-2-npiggin@gmail.com
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Nicholas Piggin authored
The POWER9 ERAT flush instruction is a SLBIA with IH=7, which is a reserved value on POWER7/8. On POWER8 this invalidates the SLB entries above index 0, similarly to SLBIA IH=0. If the SLB entries are invalidated, and then the guest is bypassed, the host SLB does not get re-loaded, so the bolted entries above 0 will be lost. This can result in kernel stack access causing a SLB fault. Kernel stack access causing a SLB fault was responsible for the infamous mega bug (search "Fix SLB reload bug"). Although since commit 48e7b769 ("powerpc/64s/hash: Convert SLB miss handlers to C") that starts using the kernel stack in the SLB miss handler, it might only result in an infinite loop of SLB faults. In any case it's a bug. Fix this by only executing the instruction on >= POWER9 where IH=7 is defined not to invalidate the SLB. POWER7/8 don't require this ERAT flush. Fixes: 50087112 ("KVM: PPC: Book3S HV: Invalidate ERAT when flushing guest TLB entries") Cc: stable@vger.kernel.org # v5.2+ Signed-off-by: Nicholas Piggin <npiggin@gmail.com> Reviewed-by: Fabiano Rosas <farosas@linux.ibm.com> Signed-off-by: Michael Ellerman <mpe@ellerman.id.au> Link: https://lore.kernel.org/r/20211119031627.577853-1-npiggin@gmail.com
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- 21 Nov, 2021 5 commits
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Linus Torvalds authored
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git://git.kernel.org/pub/scm/linux/kernel/git/tip/tipLinus Torvalds authored
Pull x86 fixes from Thomas Gleixner: - Move the command line preparation and the early command line parsing earlier so that the command line parameters which affect early_reserve_memory(), e.g. efi=nosftreserve, are taken into account. This was broken when the invocation of early_reserve_memory() was moved recently. - Use an atomic type for the SGX page accounting, which is read and written locklessly, to plug various race conditions related to it. * tag 'x86-urgent-2021-11-21' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip: x86/sgx: Fix free page accounting x86/boot: Pull up cmdline preparation and early param parsing
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git://git.kernel.org/pub/scm/linux/kernel/git/tip/tipLinus Torvalds authored
Pull x86 perf fixes from Thomas Gleixner: - Remove unneded PEBS disabling when taking LBR snapshots to prevent an unchecked MSR access error. - Fix IIO event constraints for Snowridge and Skylake server chips. * tag 'perf-urgent-2021-11-21' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip: x86/perf: Fix snapshot_branch_stack warning in VM perf/x86/intel/uncore: Fix IIO event constraints for Snowridge perf/x86/intel/uncore: Fix IIO event constraints for Skylake Server perf/x86/intel/uncore: Fix filter_tid mask for CHA events on Skylake Server
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git://git.kernel.org/pub/scm/linux/kernel/git/powerpc/linuxLinus Torvalds authored
Pull more powerpc fixes from Michael Ellerman: - Fix a bug in copying of sigset_t for 32-bit systems, which caused X to not start. - Fix handling of shared LSIs (rare) with the xive interrupt controller (Power9/10). - Fix missing TOC setup in some KVM code, which could result in oopses depending on kernel data layout. - Fix DMA mapping when we have persistent memory and only one DMA window available. - Fix further problems with STRICT_KERNEL_RWX on 8xx, exposed by a recent fix. - A couple of other minor fixes. Thanks to Alexey Kardashevskiy, Aneesh Kumar K.V, Cédric Le Goater, Christian Zigotzky, Christophe Leroy, Daniel Axtens, Finn Thain, Greg Kurz, Masahiro Yamada, Nicholas Piggin, and Uwe Kleine-König. * tag 'powerpc-5.16-2' of git://git.kernel.org/pub/scm/linux/kernel/git/powerpc/linux: powerpc/xive: Change IRQ domain to a tree domain powerpc/8xx: Fix pinned TLBs with CONFIG_STRICT_KERNEL_RWX powerpc/signal32: Fix sigset_t copy powerpc/book3e: Fix TLBCAM preset at boot powerpc/pseries/ddw: Do not try direct mapping with persistent memory and one window powerpc/pseries/ddw: simplify enable_ddw() powerpc/pseries/ddw: Revert "Extend upper limit for huge DMA window for persistent memory" powerpc/pseries: Fix numa FORM2 parsing fallback code powerpc/pseries: rename numa_dist_table to form2_distances powerpc: clean vdso32 and vdso64 directories powerpc/83xx/mpc8349emitx: Drop unused variable KVM: PPC: Book3S HV: Use GLOBAL_TOC for kvmppc_h_set_dabr/xdabr()
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Geert Uytterhoeven authored
On 32-bit: fs/pstore/blk.c: In function ‘__best_effort_init’: include/linux/kern_levels.h:5:18: warning: format ‘%zu’ expects argument of type ‘size_t’, but argument 3 has type ‘long unsigned int’ [-Wformat=] 5 | #define KERN_SOH "\001" /* ASCII Start Of Header */ | ^~~~~~ include/linux/kern_levels.h:14:19: note: in expansion of macro ‘KERN_SOH’ 14 | #define KERN_INFO KERN_SOH "6" /* informational */ | ^~~~~~~~ include/linux/printk.h:373:9: note: in expansion of macro ‘KERN_INFO’ 373 | printk(KERN_INFO pr_fmt(fmt), ##__VA_ARGS__) | ^~~~~~~~~ fs/pstore/blk.c:314:3: note: in expansion of macro ‘pr_info’ 314 | pr_info("attached %s (%zu) (no dedicated panic_write!)\n", | ^~~~~~~ Cc: stable@vger.kernel.org Fixes: 7bb9557b ("pstore/blk: Use the normal block device I/O path") Signed-off-by: Geert Uytterhoeven <geert@linux-m68k.org> Signed-off-by: Kees Cook <keescook@chromium.org> Link: https://lore.kernel.org/r/20210629103700.1935012-1-geert@linux-m68k.org Cc: Jens Axboe <axboe@kernel.dk> Reviewed-by: Christoph Hellwig <hch@lst.de> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
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- 20 Nov, 2021 7 commits
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Linus Torvalds authored
Merge misc fixes from Andrew Morton: "15 patches. Subsystems affected by this patch series: ipc, hexagon, mm (swap, slab-generic, kmemleak, hugetlb, kasan, damon, and highmem), and proc" * emailed patches from Andrew Morton <akpm@linux-foundation.org>: proc/vmcore: fix clearing user buffer by properly using clear_user() kmap_local: don't assume kmap PTEs are linear arrays in memory mm/damon/dbgfs: fix missed use of damon_dbgfs_lock mm/damon/dbgfs: use '__GFP_NOWARN' for user-specified size buffer allocation kasan: test: silence intentional read overflow warnings hugetlb, userfaultfd: fix reservation restore on userfaultfd error hugetlb: fix hugetlb cgroup refcounting during mremap mm: kmemleak: slob: respect SLAB_NOLEAKTRACE flag hexagon: ignore vmlinux.lds hexagon: clean up timer-regs.h hexagon: export raw I/O routines for modules mm: emit the "free" trace report before freeing memory in kmem_cache_free() shm: extend forced shm destroy to support objects from several IPC nses ipc: WARN if trying to remove ipc object which is absent mm/swap.c:put_pages_list(): reinitialise the page list
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git://git.kernel.dk/linux-blockLinus Torvalds authored
Pull block fixes from Jens Axboe: - Flip a cap check to avoid a selinux error (Alistair) - Fix for a regression this merge window where we can miss a queue ref put (me) - Un-mark pstore-blk as broken, as the condition that triggered that change has been rectified (Kees) - Queue quiesce and sync fixes (Ming) - FUA insertion fix (Ming) - blk-cgroup error path put fix (Yu) * tag 'block-5.16-2021-11-19' of git://git.kernel.dk/linux-block: blk-mq: don't insert FUA request with data into scheduler queue blk-cgroup: fix missing put device in error path from blkg_conf_pref() block: avoid to quiesce queue in elevator_init_mq Revert "mark pstore-blk as broken" blk-mq: cancel blk-mq dispatch work in both blk_cleanup_queue and disk_release() block: fix missing queue put in error path block: Check ADMIN before NICE for IOPRIO_CLASS_RT
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git://git.kernel.org/pub/scm/linux/kernel/git/linusw/linux-pinctrlLinus Torvalds authored
Pull pin control fixes from Linus Walleij: "There is an ACPI stubs fix which is ACKed by the ACPI maintainer for merging through my tree. One item stand out and that is that I delete the <linux/sdb.h> header that is used by nothing. I deleted this subsystem (through the GPIO tree) a while back so I feel responsible for tidying up the floor. Other than that it is the usual mistakes, a bit noisy around build issue and Kconfig then driver fixes. Specifics: - Fix some stubs causing compile issues for ACPI. - Fix some wakeups on AMD IRQs shared between GPIO and SCI. - Fix a build warning in the Tegra driver. - Fix a Kconfig issue in the Qualcomm driver. - Add a missing include the RALink driver. - Return a valid type for the Apple pinctrl IRQs. - Implement some Qualcomm SDM845 dual-edge errata. - Remove the unused <linux/sdb.h> header. (The subsystem was once deleted by the pinctrl maintainer...) - Fix a duplicate initialized in the Tegra driver. - Fix register offsets for UFS and SDC in the Qualcomm SM8350 driver" * tag 'pinctrl-v5.16-2' of git://git.kernel.org/pub/scm/linux/kernel/git/linusw/linux-pinctrl: pinctrl: qcom: sm8350: Correct UFS and SDC offsets pinctrl: tegra194: remove duplicate initializer again Remove unused header <linux/sdb.h> pinctrl: qcom: sdm845: Enable dual edge errata pinctrl: apple: Always return valid type in apple_gpio_irq_type pinctrl: ralink: include 'ralink_regs.h' in 'pinctrl-mt7620.c' pinctrl: qcom: fix unmet dependencies on GPIOLIB for GPIOLIB_IRQCHIP pinctrl: tegra: Return const pointer from tegra_pinctrl_get_group() pinctrl: amd: Fix wakeups when IRQ is shared with SCI ACPI: Add stubs for wakeup handler functions
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git://git.kernel.org/pub/scm/linux/kernel/git/s390/linuxLinus Torvalds authored
Pull s390 updates from Heiko Carstens: - Add missing Kconfig option for ftrace direct multi sample, so it can be compiled again, and also add s390 support for this sample. - Update Christian Borntraeger's email address. - Various fixes for memory layout setup. Besides other this makes it possible to load shared DCSS segments again. - Fix copy to user space of swapped kdump oldmem. - Remove -mstack-guard and -mstack-size compile options when building vdso binaries. This can happen when CONFIG_VMAP_STACK is disabled and results in broken vdso code which causes more or less random exceptions. Also remove the not needed -nostdlib option. - Fix memory leak on cpu hotplug and return code handling in kexec code. - Wire up futex_waitv system call. - Replace snprintf with sysfs_emit where appropriate. * tag 's390-5.16-3' of git://git.kernel.org/pub/scm/linux/kernel/git/s390/linux: ftrace/samples: add s390 support for ftrace direct multi sample ftrace/samples: add missing Kconfig option for ftrace direct multi sample MAINTAINERS: update email address of Christian Borntraeger s390/kexec: fix memory leak of ipl report buffer s390/kexec: fix return code handling s390/dump: fix copying to user-space of swapped kdump oldmem s390: wire up sys_futex_waitv system call s390/vdso: filter out -mstack-guard and -mstack-size s390/vdso: remove -nostdlib compiler flag s390: replace snprintf in show functions with sysfs_emit s390/boot: simplify and fix kernel memory layout setup s390/setup: re-arrange memblock setup s390/setup: avoid using memblock_enforce_memory_limit s390/setup: avoid reserving memory above identity mapping
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git://git.samba.org/sfrench/cifs-2.6Linus Torvalds authored
Pull cifs fixes from Steve French: "Three small cifs/smb3 fixes: two to address minor coverity issues and one cleanup" * tag '5.16-rc1-smb3-fixes' of git://git.samba.org/sfrench/cifs-2.6: cifs: introduce cifs_ses_mark_for_reconnect() helper cifs: protect srv_count with cifs_tcp_ses_lock cifs: move debug print out of spinlock
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David Hildenbrand authored
To clear a user buffer we cannot simply use memset, we have to use clear_user(). With a virtio-mem device that registers a vmcore_cb and has some logically unplugged memory inside an added Linux memory block, I can easily trigger a BUG by copying the vmcore via "cp": systemd[1]: Starting Kdump Vmcore Save Service... kdump[420]: Kdump is using the default log level(3). kdump[453]: saving to /sysroot/var/crash/127.0.0.1-2021-11-11-14:59:22/ kdump[458]: saving vmcore-dmesg.txt to /sysroot/var/crash/127.0.0.1-2021-11-11-14:59:22/ kdump[465]: saving vmcore-dmesg.txt complete kdump[467]: saving vmcore BUG: unable to handle page fault for address: 00007f2374e01000 #PF: supervisor write access in kernel mode #PF: error_code(0x0003) - permissions violation PGD 7a523067 P4D 7a523067 PUD 7a528067 PMD 7a525067 PTE 800000007048f867 Oops: 0003 [#1] PREEMPT SMP NOPTI CPU: 0 PID: 468 Comm: cp Not tainted 5.15.0+ #6 Hardware name: QEMU Standard PC (Q35 + ICH9, 2009), BIOS rel-1.14.0-27-g64f37cc530f1-prebuilt.qemu.org 04/01/2014 RIP: 0010:read_from_oldmem.part.0.cold+0x1d/0x86 Code: ff ff ff e8 05 ff fe ff e9 b9 e9 7f ff 48 89 de 48 c7 c7 38 3b 60 82 e8 f1 fe fe ff 83 fd 08 72 3c 49 8d 7d 08 4c 89 e9 89 e8 <49> c7 45 00 00 00 00 00 49 c7 44 05 f8 00 00 00 00 48 83 e7 f81 RSP: 0018:ffffc9000073be08 EFLAGS: 00010212 RAX: 0000000000001000 RBX: 00000000002fd000 RCX: 00007f2374e01000 RDX: 0000000000000001 RSI: 00000000ffffdfff RDI: 00007f2374e01008 RBP: 0000000000001000 R08: 0000000000000000 R09: ffffc9000073bc50 R10: ffffc9000073bc48 R11: ffffffff829461a8 R12: 000000000000f000 R13: 00007f2374e01000 R14: 0000000000000000 R15: ffff88807bd421e8 FS: 00007f2374e12140(0000) GS:ffff88807f000000(0000) knlGS:0000000000000000 CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 CR2: 00007f2374e01000 CR3: 000000007a4aa000 CR4: 0000000000350eb0 Call Trace: read_vmcore+0x236/0x2c0 proc_reg_read+0x55/0xa0 vfs_read+0x95/0x190 ksys_read+0x4f/0xc0 do_syscall_64+0x3b/0x90 entry_SYSCALL_64_after_hwframe+0x44/0xae Some x86-64 CPUs have a CPU feature called "Supervisor Mode Access Prevention (SMAP)", which is used to detect wrong access from the kernel to user buffers like this: SMAP triggers a permissions violation on wrong access. In the x86-64 variant of clear_user(), SMAP is properly handled via clac()+stac(). To fix, properly use clear_user() when we're dealing with a user buffer. Link: https://lkml.kernel.org/r/20211112092750.6921-1-david@redhat.com Fixes: 997c136f ("fs/proc/vmcore.c: add hook to read_from_oldmem() to check for non-ram pages") Signed-off-by: David Hildenbrand <david@redhat.com> Acked-by: Baoquan He <bhe@redhat.com> Cc: Dave Young <dyoung@redhat.com> Cc: Baoquan He <bhe@redhat.com> Cc: Vivek Goyal <vgoyal@redhat.com> Cc: Philipp Rudo <prudo@redhat.com> Cc: <stable@vger.kernel.org> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
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Ard Biesheuvel authored
The kmap_local conversion broke the ARM architecture, because the new code assumes that all PTEs used for creating kmaps form a linear array in memory, and uses array indexing to look up the kmap PTE belonging to a certain kmap index. On ARM, this cannot work, not only because the PTE pages may be non-adjacent in memory, but also because ARM/!LPAE interleaves hardware entries and extended entries (carrying software-only bits) in a way that is not compatible with array indexing. Fortunately, this only seems to affect configurations with more than 8 CPUs, due to the way the per-CPU kmap slots are organized in memory. Work around this by permitting an architecture to set a Kconfig symbol that signifies that the kmap PTEs do not form a lineary array in memory, and so the only way to locate the appropriate one is to walk the page tables. Link: https://lore.kernel.org/linux-arm-kernel/20211026131249.3731275-1-ardb@kernel.org/ Link: https://lkml.kernel.org/r/20211116094737.7391-1-ardb@kernel.org Fixes: 2a15ba82 ("ARM: highmem: Switch to generic kmap atomic") Signed-off-by: Ard Biesheuvel <ardb@kernel.org> Reported-by: Quanyang Wang <quanyang.wang@windriver.com> Reviewed-by: Linus Walleij <linus.walleij@linaro.org> Acked-by: Russell King (Oracle) <rmk+kernel@armlinux.org.uk> Cc: Thomas Gleixner <tglx@linutronix.de> Cc: <stable@vger.kernel.org> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
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