summaryrefslogtreecommitdiff
path: root/arch
AgeCommit message (Collapse)Author
2019-04-10x86/perf/amd: Remove need to check "running" bit in NMI handlerLendacky, Thomas
Spurious interrupt support was added to perf in the following commit, almost a decade ago: 63e6be6d98e1 ("perf, x86: Catch spurious interrupts after disabling counters") The two previous patches (resolving the race condition when disabling a PMC and NMI latency mitigation) allow for the removal of this older spurious interrupt support. Currently in x86_pmu_stop(), the bit for the PMC in the active_mask bitmap is cleared before disabling the PMC, which sets up a race condition. This race condition was mitigated by introducing the running bitmap. That race condition can be eliminated by first disabling the PMC, waiting for PMC reset on overflow and then clearing the bit for the PMC in the active_mask bitmap. The NMI handler will not re-enable a disabled counter. If x86_pmu_stop() is called from the perf NMI handler, the NMI latency mitigation support will guard against any unhandled NMI messages. Signed-off-by: Tom Lendacky <thomas.lendacky@amd.com> Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org> Cc: <stable@vger.kernel.org> # 4.14.x- Cc: Alexander Shishkin <alexander.shishkin@linux.intel.com> Cc: Arnaldo Carvalho de Melo <acme@kernel.org> Cc: Arnaldo Carvalho de Melo <acme@redhat.com> Cc: Borislav Petkov <bp@alien8.de> Cc: Jiri Olsa <jolsa@redhat.com> Cc: Linus Torvalds <torvalds@linux-foundation.org> Cc: Namhyung Kim <namhyung@kernel.org> Cc: Peter Zijlstra <peterz@infradead.org> Cc: Stephane Eranian <eranian@google.com> Cc: Thomas Gleixner <tglx@linutronix.de> Cc: Vince Weaver <vincent.weaver@maine.edu> Link: https://lkml.kernel.org/r/Message-ID: Signed-off-by: Ingo Molnar <mingo@kernel.org>
2019-04-10powerpc/mm: Define MAX_PHYSMEM_BITS for all 64-bit configsMichael Ellerman
The recent commit 8bc086899816 ("powerpc/mm: Only define MAX_PHYSMEM_BITS in SPARSEMEM configurations") removed our definition of MAX_PHYSMEM_BITS when SPARSEMEM is disabled. This inadvertently broke some 64-bit FLATMEM using configs with eg: arch/powerpc/include/asm/book3s/64/mmu-hash.h:584:6: error: "MAX_PHYSMEM_BITS" is not defined, evaluates to 0 #if (MAX_PHYSMEM_BITS > MAX_EA_BITS_PER_CONTEXT) ^~~~~~~~~~~~~~~~ Fix it by making sure we define MAX_PHYSMEM_BITS for all 64-bit configs regardless of SPARSEMEM. Fixes: 8bc086899816 ("powerpc/mm: Only define MAX_PHYSMEM_BITS in SPARSEMEM configurations") Reported-by: Andreas Schwab <schwab@linux-m68k.org> Reported-by: Hugh Dickins <hughd@google.com> Reviewed-by: Aneesh Kumar K.V <aneesh.kumar@linux.ibm.com> Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
2019-04-09Merge tag 'mips_fixes_5.1_2' of ↵Linus Torvalds
git://git.kernel.org/pub/scm/linux/kernel/git/mips/linux Pull MIPS fixes from Paul Burton: "A few minor MIPS fixes: - Provide struct pt_regs * from get_irq_regs() to kgdb_nmicallback() when handling an IPI triggered by kgdb_roundup_cpus(), matching the behavior of other architectures & resolving kgdb issues for SMP systems. - Defer a pointer dereference until after a NULL check in the irq_shutdown callback for SGI IP27 HUB interrupts. - A defconfig update for the MSCC Ocelot to enable some necessary drivers" * tag 'mips_fixes_5.1_2' of git://git.kernel.org/pub/scm/linux/kernel/git/mips/linux: MIPS: generic: Add switchdev, pinctrl and fit to ocelot_defconfig MIPS: SGI-IP27: Fix use of unchecked pointer in shutdown_bridge_irq MIPS: KGDB: fix kgdb support for SMP platforms.
2019-04-09RISC-V: Add separate defconfig for 32bit systemsAnup Patel
This patch adds rv32_defconfig for 32bit systems. The only difference between rv32_defconfig and defconfig is that rv32_defconfig has CONFIG_ARCH_RV32I=y. Signed-off-by: Anup Patel <anup.patel@wdc.com> Signed-off-by: Palmer Dabbelt <palmer@sifive.com>
2019-04-08Merge tag 'xtensa-20190408' of git://github.com/jcmvbkbc/linux-xtensaLinus Torvalds
Pull xtensa fixes from Max Filippov: - fix syscall number passed to trace_sys_exit - fix syscall number initialization in start_thread - fix level interpretation in the return_address - fix format string warning in init_pmd * tag 'xtensa-20190408' of git://github.com/jcmvbkbc/linux-xtensa: xtensa: fix format string warning in init_pmd xtensa: fix return_address xtensa: fix initialization of pt_regs::syscall in start_thread xtensa: use actual syscall number in do_syscall_trace_leave
2019-04-08arm64: backtrace: Don't bother trying to unwind the userspace stackWill Deacon
Calling dump_backtrace() with a pt_regs argument corresponding to userspace doesn't make any sense and our unwinder will simply print "Call trace:" before unwinding the stack looking for user frames. Rather than go through this song and dance, just return early if we're passed a user register state. Cc: <stable@vger.kernel.org> Fixes: 1149aad10b1e ("arm64: Add dump_backtrace() in show_regs") Reported-by: Kefeng Wang <wangkefeng.wang@huawei.com> Signed-off-by: Will Deacon <will.deacon@arm.com>
2019-04-08arm64/ftrace: fix inadvertent BUG() in trampoline checkArd Biesheuvel
The ftrace trampoline code (which deals with modules loaded out of BL range of the core kernel) uses plt_entries_equal() to check whether the per-module trampoline equals a zero buffer, to decide whether the trampoline has already been initialized. This triggers a BUG() in the opcode manipulation code, since we end up checking the ADRP offset of a 0x0 opcode, which is not an ADRP instruction. So instead, add a helper to check whether a PLT is initialized, and call that from the frace code. Cc: <stable@vger.kernel.org> # v5.0 Fixes: bdb85cd1d206 ("arm64/module: switch to ADRP/ADD sequences for PLT entries") Acked-by: Mark Rutland <mark.rutland@arm.com> Signed-off-by: Ard Biesheuvel <ard.biesheuvel@linaro.org> Signed-off-by: Will Deacon <will.deacon@arm.com>
2019-04-08powerpc/64s/radix: Fix radix segment exception handlingNicholas Piggin
Commit 48e7b76957 ("powerpc/64s/hash: Convert SLB miss handlers to C") broke the radix-mode segment exception handler. In radix mode, this is exception is not an SLB miss, rather it signals that the EA is outside the range translated by any page table. The commit lost the radix feature alternate code patch, which can cause faults to some EAs to kernel BUG at arch/powerpc/mm/slb.c:639! The original radix code would send faults to slb_miss_large_addr, which would end up faulting due to slb_addr_limit being 0. This patch sends radix directly to do_bad_slb_fault, which is a bit clearer. Fixes: 48e7b7695745 ("powerpc/64s/hash: Convert SLB miss handlers to C") Cc: stable@vger.kernel.org # v4.20+ Reported-by: Anton Blanchard <anton@samba.org> Signed-off-by: Nicholas Piggin <npiggin@gmail.com> Reviewed-by: Aneesh Kumar K.V <aneesh.kumar@linux.ibm.com> Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
2019-04-08crypto: x86/poly1305 - fix overflow during partial reductionEric Biggers
The x86_64 implementation of Poly1305 produces the wrong result on some inputs because poly1305_4block_avx2() incorrectly assumes that when partially reducing the accumulator, the bits carried from limb 'd4' to limb 'h0' fit in a 32-bit integer. This is true for poly1305-generic which processes only one block at a time. However, it's not true for the AVX2 implementation, which processes 4 blocks at a time and therefore can produce intermediate limbs about 4x larger. Fix it by making the relevant calculations use 64-bit arithmetic rather than 32-bit. Note that most of the carries already used 64-bit arithmetic, but the d4 -> h0 carry was different for some reason. To be safe I also made the same change to the corresponding SSE2 code, though that only operates on 1 or 2 blocks at a time. I don't think it's really needed for poly1305_block_sse2(), but it doesn't hurt because it's already x86_64 code. It *might* be needed for poly1305_2block_sse2(), but overflows aren't easy to reproduce there. This bug was originally detected by my patches that improve testmgr to fuzz algorithms against their generic implementation. But also add a test vector which reproduces it directly (in the AVX2 case). Fixes: b1ccc8f4b631 ("crypto: poly1305 - Add a four block AVX2 variant for x86_64") Fixes: c70f4abef07a ("crypto: poly1305 - Add a SSE2 SIMD variant for x86_64") Cc: <stable@vger.kernel.org> # v4.3+ Cc: Martin Willi <martin@strongswan.org> Cc: Jason A. Donenfeld <Jason@zx2c4.com> Signed-off-by: Eric Biggers <ebiggers@google.com> Reviewed-by: Martin Willi <martin@strongswan.org> Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>
2019-04-07Merge tag 'armsoc-fixes' of ↵Linus Torvalds
git://git.kernel.org/pub/scm/linux/kernel/git/soc/soc Pull ARM SoC fixes from Olof Johansson: "A collection of fixes from the last few weeks. Most of them are smaller tweaks and fixes to DT and hardware descriptions for boards. Some of the more significant ones are: - eMMC and RGMII stability tweaks for rk3288 - DDC fixes for Rock PI 4 - Audio fixes for two TI am335x eval boards - D_CAN clock fix for am335x - Compilation fixes for clang - !HOTPLUG_CPU compilation fix for one of the new platforms this release (milbeaut) - A revert of a gpio fix for nomadik that instead was fixed in the gpio subsystem - Whitespace fix for the DT JSON schema (no tabs allowed)" * tag 'armsoc-fixes' of git://git.kernel.org/pub/scm/linux/kernel/git/soc/soc: (25 commits) ARM: milbeaut: fix build with !CONFIG_HOTPLUG_CPU ARM: iop: don't use using 64-bit DMA masks ARM: orion: don't use using 64-bit DMA masks Revert "ARM: dts: nomadik: Fix polarity of SPI CS" dt-bindings: cpu: Fix JSON schema arm/mach-at91/pm : fix possible object reference leak ARM: dts: at91: Fix typo in ISC_D0 on PC9 ARM: dts: Fix dcan clkctrl clock for am3 reset: meson-audio-arb: Fix missing .owner setting of reset_controller_dev dt-bindings: reset: meson-g12a: Add missing USB2 PHY resets ARM: dts: rockchip: Remove #address/#size-cells from rk3288-veyron gpio-keys ARM: dts: rockchip: Remove #address/#size-cells from rk3288 mipi_dsi ARM: dts: rockchip: Fix gpu opp node names for rk3288 ARM: dts: am335x-evmsk: Correct the regulators for the audio codec ARM: dts: am335x-evm: Correct the regulators for the audio codec ARM: OMAP2+: add missing of_node_put after of_device_is_available ARM: OMAP1: ams-delta: Fix broken GPIO ID allocation arm64: dts: stratix10: add the sysmgr-syscon property from the gmac's arm64: dts: rockchip: fix rk3328 sdmmc0 write errors arm64: dts: rockchip: fix rk3328 rgmii high tx error rate ...
2019-04-07ARM: milbeaut: fix build with !CONFIG_HOTPLUG_CPUArnd Bergmann
When HOTPLUG_CPU is disabled, some fields in the smp operations are not available or needed: arch/arm/mach-milbeaut/platsmp.c:90:3: error: field designator 'cpu_die' does not refer to any field in type 'struct smp_operations' .cpu_die = m10v_cpu_die, ^ arch/arm/mach-milbeaut/platsmp.c:91:3: error: field designator 'cpu_kill' does not refer to any field in type 'struct smp_operations' .cpu_kill = m10v_cpu_kill, ^ Hide them in an #ifdef like the other platforms do. Fixes: 9fb29c734f9e ("ARM: milbeaut: Add basic support for Milbeaut m10v SoC") Signed-off-by: Arnd Bergmann <arnd@arndb.de> Signed-off-by: Olof Johansson <olof@lixom.net>
2019-04-07ARM: iop: don't use using 64-bit DMA masksArnd Bergmann
clang warns about statically defined DMA masks from the DMA_BIT_MASK macro with length 64: arch/arm/mach-iop13xx/setup.c:303:35: error: shift count >= width of type [-Werror,-Wshift-count-overflow] static u64 iop13xx_adma_dmamask = DMA_BIT_MASK(64); ^~~~~~~~~~~~~~~~ include/linux/dma-mapping.h:141:54: note: expanded from macro 'DMA_BIT_MASK' #define DMA_BIT_MASK(n) (((n) == 64) ? ~0ULL : ((1ULL<<(n))-1)) ^ ~~~ The ones in iop shouldn't really be 64 bit masks, so changing them to what the driver can support avoids the warning. Signed-off-by: Arnd Bergmann <arnd@arndb.de> Signed-off-by: Olof Johansson <olof@lixom.net>
2019-04-07ARM: orion: don't use using 64-bit DMA masksArnd Bergmann
clang warns about statically defined DMA masks from the DMA_BIT_MASK macro with length 64: arch/arm/plat-orion/common.c:625:29: error: shift count >= width of type [-Werror,-Wshift-count-overflow] .coherent_dma_mask = DMA_BIT_MASK(64), ^~~~~~~~~~~~~~~~ include/linux/dma-mapping.h:141:54: note: expanded from macro 'DMA_BIT_MASK' #define DMA_BIT_MASK(n) (((n) == 64) ? ~0ULL : ((1ULL<<(n))-1)) The ones in orion shouldn't really be 64 bit masks, so changing them to what the driver can support avoids the warning. Signed-off-by: Arnd Bergmann <arnd@arndb.de> Signed-off-by: Olof Johansson <olof@lixom.net>
2019-04-07Revert "ARM: dts: nomadik: Fix polarity of SPI CS"Olof Johansson
This reverts commit fa9463564e77067df81b0b8dec91adbbbc47bfb4. Per Linus Walleij: Dear ARM SoC maintainers, can you please revert this patch. It was the wrong solution to the wrong problem, and I must have acted in stress. Andrey fixed the real bug in a proper way in these commits: commit e5545c94e43b8f6599ffc01df8d1aedf18ee912a "gpio: of: Check propname before applying "cs-gpios" quirks" commit 7ce40277bf848391705011ba37eac2e377cbd9e6 "gpio: of: Check for "spi-cs-high" in child instead of parent node" Signed-off-by: Olof Johansson <olof@lixom.net>
2019-04-07Merge tag 'omap-for-v5.1/fixes-signed' of ↵Olof Johansson
git://git.kernel.org/pub/scm/linux/kernel/git/tmlind/linux-omap into arm/fixes Fixes for omaps for v5.1-rc cycle Few small fixes for omap variants: - Fix ams-delta gpio IDs - Add missing of_node_put for omapdss platform init code - Fix unconfigured audio regulators for two am335x boards - Fix use of wrong offset for am335x d_can clocks * tag 'omap-for-v5.1/fixes-signed' of git://git.kernel.org/pub/scm/linux/kernel/git/tmlind/linux-omap: ARM: dts: Fix dcan clkctrl clock for am3 ARM: dts: am335x-evmsk: Correct the regulators for the audio codec ARM: dts: am335x-evm: Correct the regulators for the audio codec ARM: OMAP2+: add missing of_node_put after of_device_is_available ARM: OMAP1: ams-delta: Fix broken GPIO ID allocation Signed-off-by: Olof Johansson <olof@lixom.net>
2019-04-07Merge tag 'at91-5.1-fixes' of ↵Olof Johansson
git://git.kernel.org/pub/scm/linux/kernel/git/at91/linux into arm/fixes AT91 fixes for 5.1 - fix a typo in sama5d2 pinmuxing which concerns the ISC data 0 signal - fix a kobject reference leak * tag 'at91-5.1-fixes' of git://git.kernel.org/pub/scm/linux/kernel/git/at91/linux: arm/mach-at91/pm : fix possible object reference leak ARM: dts: at91: Fix typo in ISC_D0 on PC9 Signed-off-by: Olof Johansson <olof@lixom.net>
2019-04-07Merge tag 'v5.1-rockchip-dtfixes-1' of ↵Olof Johansson
git://git.kernel.org/pub/scm/linux/kernel/git/mmind/linux-rockchip into arm/fixes Fixes for dtc warnings, fixes for ethernet transfers on rk3328, sd-card related fixes on both rk3328 ans rk3288-tinker and a regulator fix on rock64 and making ddc actually work on the Rock PI 4 due to missing the ddc bus. * tag 'v5.1-rockchip-dtfixes-1' of git://git.kernel.org/pub/scm/linux/kernel/git/mmind/linux-rockchip: ARM: dts: rockchip: Remove #address/#size-cells from rk3288-veyron gpio-keys ARM: dts: rockchip: Remove #address/#size-cells from rk3288 mipi_dsi ARM: dts: rockchip: Fix gpu opp node names for rk3288 arm64: dts: rockchip: fix rk3328 sdmmc0 write errors arm64: dts: rockchip: fix rk3328 rgmii high tx error rate ARM: dts: rockchip: Fix SD card detection on rk3288-tinker arm64: dts: rockchip: Fix vcc_host1_5v GPIO polarity on rk3328-rock64 ARM: dts: rockchip: fix rk3288 cpu opp node reference arm64: dts: rockchip: add DDC bus on Rock Pi 4 arm64: dts: rockchip: fix rk3328-roc-cc gmac2io tx/rx_delay Signed-off-by: Olof Johansson <olof@lixom.net>
2019-04-07Merge tag 'stratix10_fix_for_v5.1' of ↵Olof Johansson
git://git.kernel.org/pub/scm/linux/kernel/git/dinguyen/linux into arm/fixes arm64: dts: stratix10: fix emac loading warning - Add missing "altr,sysmgr-syscon" property to all gmac nodes * tag 'stratix10_fix_for_v5.1' of git://git.kernel.org/pub/scm/linux/kernel/git/dinguyen/linux: arm64: dts: stratix10: add the sysmgr-syscon property from the gmac's Signed-off-by: Olof Johansson <olof@lixom.net>
2019-04-08powerpc/vdso32: fix CLOCK_MONOTONIC on PPC64Christophe Leroy
Commit b5b4453e7912 ("powerpc/vdso64: Fix CLOCK_MONOTONIC inconsistencies across Y2038") changed the type of wtom_clock_sec to s64 on PPC64. Therefore, VDSO32 needs to read it with a 4 bytes shift in order to retrieve the lower part of it. Fixes: b5b4453e7912 ("powerpc/vdso64: Fix CLOCK_MONOTONIC inconsistencies across Y2038") Reported-by: Christian Zigotzky <chzigotzky@xenosoft.de> Signed-off-by: Christophe Leroy <christophe.leroy@c-s.fr> Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
2019-04-07Merge tag 'for-linus-5.1b-rc4-tag' of ↵Linus Torvalds
git://git.kernel.org/pub/scm/linux/kernel/git/xen/tip Pull xen fixes from Juergen Gross: "One minor fix and a small cleanup for the xen privcmd driver" * tag 'for-linus-5.1b-rc4-tag' of git://git.kernel.org/pub/scm/linux/kernel/git/xen/tip: xen: Prevent buffer overflow in privcmd ioctl xen: use struct_size() helper in kzalloc()
2019-04-06parisc: Detect QEMU earlier in boot processHelge Deller
While adding LASI support to QEMU, I noticed that the QEMU detection in the kernel happens much too late. For example, when a LASI chip is found by the kernel, it registers the LASI LED driver as well. But when we run on QEMU it makes sense to avoid spending unnecessary CPU cycles, so we need to access the running_on_QEMU flag earlier than before. This patch now makes the QEMU detection the fist task of the Linux kernel by moving it to where the kernel enters the C-coding. Fixes: 310d82784fb4 ("parisc: qemu idle sleep support") Signed-off-by: Helge Deller <deller@gmx.de> Cc: stable@vger.kernel.org # v4.14+
2019-04-06parisc: also set iaoq_b in instruction_pointer_set()Sven Schnelle
When setting the instruction pointer on PA-RISC we also need to set the back of the instruction queue to the new offset, otherwise we will execute on instruction from the new location, and jumping back to the old location stored in iaoq_b. Signed-off-by: Sven Schnelle <svens@stackframe.org> Signed-off-by: Helge Deller <deller@gmx.de> Fixes: 75ebedf1d263 ("parisc: Add HAVE_REGS_AND_STACK_ACCESS_API feature") Cc: stable@vger.kernel.org # 4.19+
2019-04-06parisc: regs_return_value() should return gpr28Sven Schnelle
While working on kretprobes for PA-RISC I was wondering while the kprobes sanity test always fails on kretprobes. This is caused by returning gpr20 instead of gpr28. Signed-off-by: Sven Schnelle <svens@stackframe.org> Signed-off-by: Helge Deller <deller@gmx.de> Cc: stable@vger.kernel.org # 4.14+
2019-04-06block: remove CONFIG_LBDAFChristoph Hellwig
Currently support for 64-bit sector_t and blkcnt_t is optional on 32-bit architectures. These types are required to support block device and/or file sizes larger than 2 TiB, and have generally defaulted to on for a long time. Enabling the option only increases the i386 tinyconfig size by 145 bytes, and many data structures already always use 64-bit values for their in-core and on-disk data structures anyway, so there should not be a large change in dynamic memory usage either. Dropping this option removes a somewhat weird non-default config that has cause various bugs or compiler warnings when actually used. Signed-off-by: Christoph Hellwig <hch@lst.de> Signed-off-by: Jens Axboe <axboe@kernel.dk>
2019-04-06x86/asm: Use stricter assembly constraints in bitopsAlexander Potapenko
There's a number of problems with how arch/x86/include/asm/bitops.h is currently using assembly constraints for the memory region bitops are modifying: 1) Use memory clobber in bitops that touch arbitrary memory Certain bit operations that read/write bits take a base pointer and an arbitrarily large offset to address the bit relative to that base. Inline assembly constraints aren't expressive enough to tell the compiler that the assembly directive is going to touch a specific memory location of unknown size, therefore we have to use the "memory" clobber to indicate that the assembly is going to access memory locations other than those listed in the inputs/outputs. To indicate that BTR/BTS instructions don't necessarily touch the first sizeof(long) bytes of the argument, we also move the address to assembly inputs. This particular change leads to size increase of 124 kernel functions in a defconfig build. For some of them the diff is in NOP operations, other end up re-reading values from memory and may potentially slow down the execution. But without these clobbers the compiler is free to cache the contents of the bitmaps and use them as if they weren't changed by the inline assembly. 2) Use byte-sized arguments for operations touching single bytes. Passing a long value to ANDB/ORB/XORB instructions makes the compiler treat sizeof(long) bytes as being clobbered, which isn't the case. This may theoretically lead to worse code in the case of heavy optimization. Practical impact: I've built a defconfig kernel and looked through some of the functions generated by GCC 7.3.0 with and without this clobber, and didn't spot any miscompilations. However there is a (trivial) theoretical case where this code leads to miscompilation: https://lkml.org/lkml/2019/3/28/393 using just GCC 8.3.0 with -O2. It isn't hard to imagine someone writes such a function in the kernel someday. So the primary motivation is to fix an existing misuse of the asm directive, which happens to work in certain configurations now, but isn't guaranteed to work under different circumstances. [ --mingo: Added -stable tag because defconfig only builds a fraction of the kernel and the trivial testcase looks normal enough to be used in existing or in-development code. ] Signed-off-by: Alexander Potapenko <glider@google.com> Cc: <stable@vger.kernel.org> Cc: Andy Lutomirski <luto@kernel.org> Cc: Borislav Petkov <bp@alien8.de> Cc: Brian Gerst <brgerst@gmail.com> Cc: Denys Vlasenko <dvlasenk@redhat.com> Cc: Dmitry Vyukov <dvyukov@google.com> Cc: H. Peter Anvin <hpa@zytor.com> Cc: James Y Knight <jyknight@google.com> Cc: Linus Torvalds <torvalds@linux-foundation.org> Cc: Paul E. McKenney <paulmck@linux.ibm.com> Cc: Peter Zijlstra <peterz@infradead.org> Cc: Thomas Gleixner <tglx@linutronix.de> Link: http://lkml.kernel.org/r/20190402112813.193378-1-glider@google.com [ Edited the changelog, tidied up one of the defines. ] Signed-off-by: Ingo Molnar <mingo@kernel.org>
2019-04-05Merge branch 'akpm' (patches from Andrew)Linus Torvalds
Merge misc fixes from Andrew Morton: "14 fixes" * emailed patches from Andrew Morton <akpm@linux-foundation.org>: kernel/sysctl.c: fix out-of-bounds access when setting file-max mm/util.c: fix strndup_user() comment sh: fix multiple function definition build errors MAINTAINERS: add maintainer and replacing reviewer ARM/NUVOTON NPCM MAINTAINERS: fix bad pattern in ARM/NUVOTON NPCM mm: writeback: use exact memcg dirty counts psi: clarify the units used in pressure files mm/huge_memory.c: fix modifying of page protection by insert_pfn_pmd() hugetlbfs: fix memory leak for resv_map mm: fix vm_fault_t cast in VM_FAULT_GET_HINDEX() lib/lzo: fix bugs for very short or empty input include/linux/bitrev.h: fix constant bitrev kmemleak: powerpc: skip scanning holes in the .bss section lib/string.c: implement a basic bcmp
2019-04-05sh: fix multiple function definition build errorsRandy Dunlap
Many of the sh CPU-types have their own plat_irq_setup() and arch_init_clk_ops() functions, so these same (empty) functions in arch/sh/boards/of-generic.c are not needed and cause build errors. If there is some case where these empty functions are needed, they can be retained by marking them as "__weak" while at the same time making builds that do not need them succeed. Fixes these build errors: arch/sh/boards/of-generic.o: In function `plat_irq_setup': (.init.text+0x134): multiple definition of `plat_irq_setup' arch/sh/kernel/cpu/sh2/setup-sh7619.o:(.init.text+0x30): first defined here arch/sh/boards/of-generic.o: In function `arch_init_clk_ops': (.init.text+0x118): multiple definition of `arch_init_clk_ops' arch/sh/kernel/cpu/sh2/clock-sh7619.o:(.init.text+0x0): first defined here Link: http://lkml.kernel.org/r/9ee4e0c5-f100-86a2-bd4d-1d3287ceab31@infradead.org Signed-off-by: Randy Dunlap <rdunlap@infradead.org> Reported-by: kbuild test robot <lkp@intel.com> Cc: Takashi Iwai <tiwai@suse.de> Cc: Yoshinori Sato <ysato@users.sourceforge.jp> Cc: Rich Felker <dalias@libc.org> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2019-04-05kmemleak: powerpc: skip scanning holes in the .bss sectionCatalin Marinas
Commit 2d4f567103ff ("KVM: PPC: Introduce kvm_tmp framework") adds kvm_tmp[] into the .bss section and then free the rest of unused spaces back to the page allocator. kernel_init kvm_guest_init kvm_free_tmp free_reserved_area free_unref_page free_unref_page_prepare With DEBUG_PAGEALLOC=y, it will unmap those pages from kernel. As the result, kmemleak scan will trigger a panic when it scans the .bss section with unmapped pages. This patch creates dedicated kmemleak objects for the .data, .bss and potentially .data..ro_after_init sections to allow partial freeing via the kmemleak_free_part() in the powerpc kvm_free_tmp() function. Link: http://lkml.kernel.org/r/20190321171917.62049-1-catalin.marinas@arm.com Signed-off-by: Catalin Marinas <catalin.marinas@arm.com> Reported-by: Qian Cai <cai@lca.pw> Acked-by: Michael Ellerman <mpe@ellerman.id.au> (powerpc) Tested-by: Qian Cai <cai@lca.pw> Cc: Paul Mackerras <paulus@samba.org> Cc: Benjamin Herrenschmidt <benh@kernel.crashing.org> Cc: Avi Kivity <avi@redhat.com> Cc: Paolo Bonzini <pbonzini@redhat.com> Cc: Radim Krcmar <rkrcmar@redhat.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2019-04-05Merge tag 'for-linus' of git://git.kernel.org/pub/scm/virt/kvm/kvmLinus Torvalds
Pull kvm fixes from Paolo Bonzini: "x86 fixes for overflows and other nastiness" * tag 'for-linus' of git://git.kernel.org/pub/scm/virt/kvm/kvm: KVM: x86: nVMX: fix x2APIC VTPR read intercept KVM: x86: nVMX: close leak of L0's x2APIC MSRs (CVE-2019-3887) KVM: SVM: prevent DBG_DECRYPT and DBG_ENCRYPT overflow kvm: svm: fix potential get_num_contig_pages overflow
2019-04-05Merge tag 'arm64-fixes' of ↵Linus Torvalds
git://git.kernel.org/pub/scm/linux/kernel/git/arm64/linux Pull arm64 fix from Catalin Marinas: "Fix unwind_frame() in the context of pseudo NMI" * tag 'arm64-fixes' of git://git.kernel.org/pub/scm/linux/kernel/git/arm64/linux: arm64: fix wrong check of on_sdei_stack in nmi context
2019-04-05Merge tag 'trace-5.1-rc3' of ↵Linus Torvalds
git://git.kernel.org/pub/scm/linux/kernel/git/rostedt/linux-trace Pull syscall-get-arguments cleanup and fixes from Steven Rostedt: "Andy Lutomirski approached me to tell me that the syscall_get_arguments() implementation in x86 was horrible and gcc certainly gets it wrong. He said that since the tracepoints only pass in 0 and 6 for i and n repectively, it should be optimized for that case. Inspecting the kernel, I discovered that all users pass in 0 for i and only one file passing in something other than 6 for the number of arguments. That code happens to be my own code used for the special syscall tracing. That can easily be converted to just using 0 and 6 as well, and only copying what is needed. Which is probably the faster path anyway for that case. Along the way, a couple of real fixes came from this as the syscall_get_arguments() function was incorrect for csky and riscv. x86 has been optimized to for the new interface that removes the variable number of arguments, but the other architectures could still use some loving and take more advantage of the simpler interface" * tag 'trace-5.1-rc3' of git://git.kernel.org/pub/scm/linux/kernel/git/rostedt/linux-trace: syscalls: Remove start and number from syscall_set_arguments() args syscalls: Remove start and number from syscall_get_arguments() args csky: Fix syscall_get_arguments() and syscall_set_arguments() riscv: Fix syscall_get_arguments() and syscall_set_arguments() tracing/syscalls: Pass in hardcoded 6 into syscall_get_arguments() ptrace: Remove maxargs from task_current_syscall()
2019-04-05KVM: x86: nVMX: fix x2APIC VTPR read interceptMarc Orr
Referring to the "VIRTUALIZING MSR-BASED APIC ACCESSES" chapter of the SDM, when "virtualize x2APIC mode" is 1 and "APIC-register virtualization" is 0, a RDMSR of 808H should return the VTPR from the virtual APIC page. However, for nested, KVM currently fails to disable the read intercept for this MSR. This means that a RDMSR exit takes precedence over "virtualize x2APIC mode", and KVM passes through L1's TPR to L2, instead of sourcing the value from L2's virtual APIC page. This patch fixes the issue by disabling the read intercept, in VMCS02, for the VTPR when "APIC-register virtualization" is 0. The issue described above and fix prescribed here, were verified with a related patch in kvm-unit-tests titled "Test VMX's virtualize x2APIC mode w/ nested". Signed-off-by: Marc Orr <marcorr@google.com> Reviewed-by: Jim Mattson <jmattson@google.com> Fixes: c992384bde84f ("KVM: vmx: speed up MSR bitmap merge") Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
2019-04-05KVM: x86: nVMX: close leak of L0's x2APIC MSRs (CVE-2019-3887)Marc Orr
The nested_vmx_prepare_msr_bitmap() function doesn't directly guard the x2APIC MSR intercepts with the "virtualize x2APIC mode" MSR. As a result, we discovered the potential for a buggy or malicious L1 to get access to L0's x2APIC MSRs, via an L2, as follows. 1. L1 executes WRMSR(IA32_SPEC_CTRL, 1). This causes the spec_ctrl variable, in nested_vmx_prepare_msr_bitmap() to become true. 2. L1 disables "virtualize x2APIC mode" in VMCS12. 3. L1 enables "APIC-register virtualization" in VMCS12. Now, KVM will set VMCS02's x2APIC MSR intercepts from VMCS12, and then set "virtualize x2APIC mode" to 0 in VMCS02. Oops. This patch closes the leak by explicitly guarding VMCS02's x2APIC MSR intercepts with VMCS12's "virtualize x2APIC mode" control. The scenario outlined above and fix prescribed here, were verified with a related patch in kvm-unit-tests titled "Add leak scenario to virt_x2apic_mode_test". Note, it looks like this issue may have been introduced inadvertently during a merge---see 15303ba5d1cd. Signed-off-by: Marc Orr <marcorr@google.com> Reviewed-by: Jim Mattson <jmattson@google.com> Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
2019-04-05KVM: SVM: prevent DBG_DECRYPT and DBG_ENCRYPT overflowDavid Rientjes
This ensures that the address and length provided to DBG_DECRYPT and DBG_ENCRYPT do not cause an overflow. At the same time, pass the actual number of pages pinned in memory to sev_unpin_memory() as a cleanup. Reported-by: Cfir Cohen <cfir@google.com> Signed-off-by: David Rientjes <rientjes@google.com> Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
2019-04-05kvm: svm: fix potential get_num_contig_pages overflowDavid Rientjes
get_num_contig_pages() could potentially overflow int so make its type consistent with its usage. Reported-by: Cfir Cohen <cfir@google.com> Cc: stable@vger.kernel.org Signed-off-by: David Rientjes <rientjes@google.com> Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
2019-04-05syscalls: Remove start and number from syscall_set_arguments() argsSteven Rostedt (VMware)
After removing the start and count arguments of syscall_get_arguments() it seems reasonable to remove them from syscall_set_arguments(). Note, as of today, there are no users of syscall_set_arguments(). But we are told that there will be soon. But for now, at least make it consistent with syscall_get_arguments(). Link: http://lkml.kernel.org/r/20190327222014.GA32540@altlinux.org Cc: Oleg Nesterov <oleg@redhat.com> Cc: Kees Cook <keescook@chromium.org> Cc: Andy Lutomirski <luto@amacapital.net> Cc: Dominik Brodowski <linux@dominikbrodowski.net> Cc: Dave Martin <dave.martin@arm.com> Cc: "Dmitry V. Levin" <ldv@altlinux.org> Cc: x86@kernel.org Cc: linux-snps-arc@lists.infradead.org Cc: linux-kernel@vger.kernel.org Cc: linux-arm-kernel@lists.infradead.org Cc: linux-c6x-dev@linux-c6x.org Cc: uclinux-h8-devel@lists.sourceforge.jp Cc: linux-hexagon@vger.kernel.org Cc: linux-ia64@vger.kernel.org Cc: linux-mips@vger.kernel.org Cc: nios2-dev@lists.rocketboards.org Cc: openrisc@lists.librecores.org Cc: linux-parisc@vger.kernel.org Cc: linuxppc-dev@lists.ozlabs.org Cc: linux-riscv@lists.infradead.org Cc: linux-s390@vger.kernel.org Cc: linux-sh@vger.kernel.org Cc: sparclinux@vger.kernel.org Cc: linux-um@lists.infradead.org Cc: linux-xtensa@linux-xtensa.org Cc: linux-arch@vger.kernel.org Acked-by: Max Filippov <jcmvbkbc@gmail.com> # For xtensa changes Acked-by: Will Deacon <will.deacon@arm.com> # For the arm64 bits Reviewed-by: Thomas Gleixner <tglx@linutronix.de> # for x86 Reviewed-by: Dmitry V. Levin <ldv@altlinux.org> Signed-off-by: Steven Rostedt (VMware) <rostedt@goodmis.org>
2019-04-05syscalls: Remove start and number from syscall_get_arguments() argsSteven Rostedt (Red Hat)
At Linux Plumbers, Andy Lutomirski approached me and pointed out that the function call syscall_get_arguments() implemented in x86 was horribly written and not optimized for the standard case of passing in 0 and 6 for the starting index and the number of system calls to get. When looking at all the users of this function, I discovered that all instances pass in only 0 and 6 for these arguments. Instead of having this function handle different cases that are never used, simply rewrite it to return the first 6 arguments of a system call. This should help out the performance of tracing system calls by ptrace, ftrace and perf. Link: http://lkml.kernel.org/r/20161107213233.754809394@goodmis.org Cc: Oleg Nesterov <oleg@redhat.com> Cc: Kees Cook <keescook@chromium.org> Cc: Andy Lutomirski <luto@amacapital.net> Cc: Dominik Brodowski <linux@dominikbrodowski.net> Cc: Dave Martin <dave.martin@arm.com> Cc: "Dmitry V. Levin" <ldv@altlinux.org> Cc: x86@kernel.org Cc: linux-snps-arc@lists.infradead.org Cc: linux-kernel@vger.kernel.org Cc: linux-arm-kernel@lists.infradead.org Cc: linux-c6x-dev@linux-c6x.org Cc: uclinux-h8-devel@lists.sourceforge.jp Cc: linux-hexagon@vger.kernel.org Cc: linux-ia64@vger.kernel.org Cc: linux-mips@vger.kernel.org Cc: nios2-dev@lists.rocketboards.org Cc: openrisc@lists.librecores.org Cc: linux-parisc@vger.kernel.org Cc: linuxppc-dev@lists.ozlabs.org Cc: linux-riscv@lists.infradead.org Cc: linux-s390@vger.kernel.org Cc: linux-sh@vger.kernel.org Cc: sparclinux@vger.kernel.org Cc: linux-um@lists.infradead.org Cc: linux-xtensa@linux-xtensa.org Cc: linux-arch@vger.kernel.org Acked-by: Paul Burton <paul.burton@mips.com> # MIPS parts Acked-by: Max Filippov <jcmvbkbc@gmail.com> # For xtensa changes Acked-by: Will Deacon <will.deacon@arm.com> # For the arm64 bits Reviewed-by: Thomas Gleixner <tglx@linutronix.de> # for x86 Reviewed-by: Dmitry V. Levin <ldv@altlinux.org> Reported-by: Andy Lutomirski <luto@amacapital.net> Signed-off-by: Steven Rostedt (VMware) <rostedt@goodmis.org>
2019-04-05xen: Prevent buffer overflow in privcmd ioctlDan Carpenter
The "call" variable comes from the user in privcmd_ioctl_hypercall(). It's an offset into the hypercall_page[] which has (PAGE_SIZE / 32) elements. We need to put an upper bound on it to prevent an out of bounds access. Cc: stable@vger.kernel.org Fixes: 1246ae0bb992 ("xen: add variable hypercall caller") Signed-off-by: Dan Carpenter <dan.carpenter@oracle.com> Reviewed-by: Boris Ostrovsky <boris.ostrovsky@oracle.com> Signed-off-by: Juergen Gross <jgross@suse.com>
2019-04-04xtensa: fix format string warning in init_pmdMax Filippov
Use %lu instead of %zu to fix the following warning introduced with recent memblock refactoring: xtensa/mm/mmu.c:36:9: warning: format '%zu' expects argument of type 'size_t', but argument 3 has type 'long unsigned int Signed-off-by: Max Filippov <jcmvbkbc@gmail.com>
2019-04-04Merge tag 'riscv-for-linus-5.1-rc4' of ↵Linus Torvalds
git://git.kernel.org/pub/scm/linux/kernel/git/palmer/riscv-linux Pull RISC-V fixes from Palmer Dabbelt: "I dropped the ball a bit here: these patches should all probably have been part of rc2, but I wanted to get around to properly testing them in the various configurations (qemu32, qeum64, unleashed) first. Unfortunately I've been traveling and didn't have time to actually do that, but since these fix concrete bugs and pass my old set of tests I don't want to delay the fixes any longer. There are four independent fixes here: - A fix for the rv32 port that corrects the 64-bit user accesor's fixup label address. - A fix for a regression introduced during the merge window that broke medlow configurations at run time. This patch also includes a fix that disables ftrace for the same set of functions, which was found by inspection at the same time. - A modification of the memory map to avoid overlapping the FIXMAP and VMALLOC regions on systems with small memory maps. - A fix to the module handling code to use the correct syntax for probing Kconfig entries. These have passed my standard test flow, but I didn't have time to expand that testing like I said I would" * tag 'riscv-for-linus-5.1-rc4' of git://git.kernel.org/pub/scm/linux/kernel/git/palmer/riscv-linux: RISC-V: Use IS_ENABLED(CONFIG_CMODEL_MEDLOW) RISC-V: Fix FIXMAP_TOP to avoid overlap with VMALLOC area RISC-V: Always compile mm/init.c with cmodel=medany and notrace riscv: fix accessing 8-byte variable from RV32
2019-04-04xtensa: fix return_addressMax Filippov
return_address returns the address that is one level higher in the call stack than requested in its argument, because level 0 corresponds to its caller's return address. Use requested level as the number of stack frames to skip. This fixes the address reported by might_sleep and friends. Cc: stable@vger.kernel.org Signed-off-by: Max Filippov <jcmvbkbc@gmail.com>
2019-04-04MIPS: generic: Add switchdev, pinctrl and fit to ocelot_defconfigHoratiu Vultur
Some of the configuration were not selected by default anymore, therefore enable them again. Also remove some configs which are used for MSCC Ocelot. Signed-off-by: Horatiu Vultur <horatiu.vultur@microchip.com> Signed-off-by: Paul Burton <paul.burton@mips.com> Cc: <alexandre.belloni@bootlin.com> Cc: <UNGLinuxDriver@microchip.com> Cc: <ralf@linux-mips.org> Cc: <jhogan@kernel.org> Cc: <linux-mips@vger.kernel.org> Cc: <linux-kernel@vger.kernel.org>
2019-04-04arm64: fix wrong check of on_sdei_stack in nmi contextWei Li
When doing unwind_frame() in the context of pseudo nmi (need enable CONFIG_ARM64_PSEUDO_NMI), reaching the bottom of the stack (fp == 0, pc != 0), function on_sdei_stack() will return true while the sdei acpi table is not inited in fact. This will cause a "NULL pointer dereference" oops when going on. Reviewed-by: Julien Thierry <julien.thierry@arm.com> Signed-off-by: Wei Li <liwei391@huawei.com> Signed-off-by: Catalin Marinas <catalin.marinas@arm.com>
2019-04-04csky: Fix syscall_get_arguments() and syscall_set_arguments()Dmitry V. Levin
C-SKY syscall arguments are located in orig_a0,a1,a2,a3,regs[0],regs[1] fields of struct pt_regs. Due to an off-by-one bug and a bug in pointer arithmetic syscall_get_arguments() was reading orig_a0,regs[1..5] fields instead. Likewise, syscall_set_arguments() was writing orig_a0,regs[1..5] fields instead. Link: http://lkml.kernel.org/r/20190329171230.GB32456@altlinux.org Fixes: 4859bfca11c7d ("csky: System Call") Cc: Ingo Molnar <mingo@redhat.com> Cc: Kees Cook <keescook@chromium.org> Cc: Andy Lutomirski <luto@amacapital.net> Cc: Will Drewry <wad@chromium.org> Cc: stable@vger.kernel.org # v4.20+ Tested-by: Guo Ren <ren_guo@c-sky.com> Acked-by: Guo Ren <ren_guo@c-sky.com> Signed-off-by: Dmitry V. Levin <ldv@altlinux.org> Signed-off-by: Steven Rostedt (VMware) <rostedt@goodmis.org>
2019-04-04riscv: Fix syscall_get_arguments() and syscall_set_arguments()Dmitry V. Levin
RISC-V syscall arguments are located in orig_a0,a1..a5 fields of struct pt_regs. Due to an off-by-one bug and a bug in pointer arithmetic syscall_get_arguments() was reading s3..s7 fields instead of a1..a5. Likewise, syscall_set_arguments() was writing s3..s7 fields instead of a1..a5. Link: http://lkml.kernel.org/r/20190329171221.GA32456@altlinux.org Fixes: e2c0cdfba7f69 ("RISC-V: User-facing API") Cc: Ingo Molnar <mingo@redhat.com> Cc: Kees Cook <keescook@chromium.org> Cc: Andy Lutomirski <luto@amacapital.net> Cc: Will Drewry <wad@chromium.org> Cc: Albert Ou <aou@eecs.berkeley.edu> Cc: linux-riscv@lists.infradead.org Cc: stable@vger.kernel.org # v4.15+ Acked-by: Palmer Dabbelt <palmer@sifive.com> Signed-off-by: Dmitry V. Levin <ldv@altlinux.org> Signed-off-by: Steven Rostedt (VMware) <rostedt@goodmis.org>
2019-04-04arm/mach-at91/pm : fix possible object reference leakPeng Hao
of_find_device_by_node() takes a reference to the struct device when it finds a match via get_device. When returning error we should call put_device. Reviewed-by: Mukesh Ojha <mojha@codeaurora.org> Signed-off-by: Peng Hao <peng.hao2@zte.com.cn> Signed-off-by: Ludovic Desroches <ludovic.desroches@microchip.com>
2019-04-03xtensa: fix initialization of pt_regs::syscall in start_threadMax Filippov
New pt_regs should indicate that there's no syscall, not that there's syscall #0. While at it wrap macro body in do/while and parenthesize macro arguments. Signed-off-by: Max Filippov <jcmvbkbc@gmail.com>
2019-04-03xtensa: use actual syscall number in do_syscall_trace_leaveMax Filippov
Syscall may alter pt_regs structure passed to it, resulting in a mismatch between syscall entry end syscall exit entries in the ftrace. Temporary restore syscall field of the pt_regs for the duration of do_syscall_trace_leave. Signed-off-by: Max Filippov <jcmvbkbc@gmail.com>
2019-04-03x86/perf/amd: Resolve NMI latency issues for active PMCsLendacky, Thomas
On AMD processors, the detection of an overflowed PMC counter in the NMI handler relies on the current value of the PMC. So, for example, to check for overflow on a 48-bit counter, bit 47 is checked to see if it is 1 (not overflowed) or 0 (overflowed). When the perf NMI handler executes it does not know in advance which PMC counters have overflowed. As such, the NMI handler will process all active PMC counters that have overflowed. NMI latency in newer AMD processors can result in multiple overflowed PMC counters being processed in one NMI and then a subsequent NMI, that does not appear to be a back-to-back NMI, not finding any PMC counters that have overflowed. This may appear to be an unhandled NMI resulting in either a panic or a series of messages, depending on how the kernel was configured. To mitigate this issue, add an AMD handle_irq callback function, amd_pmu_handle_irq(), that will invoke the common x86_pmu_handle_irq() function and upon return perform some additional processing that will indicate if the NMI has been handled or would have been handled had an earlier NMI not handled the overflowed PMC. Using a per-CPU variable, a minimum value of the number of active PMCs or 2 will be set whenever a PMC is active. This is used to indicate the possible number of NMIs that can still occur. The value of 2 is used for when an NMI does not arrive at the LAPIC in time to be collapsed into an already pending NMI. Each time the function is called without having handled an overflowed counter, the per-CPU value is checked. If the value is non-zero, it is decremented and the NMI indicates that it handled the NMI. If the value is zero, then the NMI indicates that it did not handle the NMI. Signed-off-by: Tom Lendacky <thomas.lendacky@amd.com> Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org> Cc: <stable@vger.kernel.org> # 4.14.x- Cc: Alexander Shishkin <alexander.shishkin@linux.intel.com> Cc: Arnaldo Carvalho de Melo <acme@kernel.org> Cc: Arnaldo Carvalho de Melo <acme@redhat.com> Cc: Borislav Petkov <bp@alien8.de> Cc: Jiri Olsa <jolsa@redhat.com> Cc: Linus Torvalds <torvalds@linux-foundation.org> Cc: Namhyung Kim <namhyung@kernel.org> Cc: Peter Zijlstra <peterz@infradead.org> Cc: Stephane Eranian <eranian@google.com> Cc: Thomas Gleixner <tglx@linutronix.de> Cc: Vince Weaver <vincent.weaver@maine.edu> Link: https://lkml.kernel.org/r/Message-ID: Signed-off-by: Ingo Molnar <mingo@kernel.org>
2019-04-03x86/perf/amd: Resolve race condition when disabling PMCLendacky, Thomas
On AMD processors, the detection of an overflowed counter in the NMI handler relies on the current value of the counter. So, for example, to check for overflow on a 48 bit counter, bit 47 is checked to see if it is 1 (not overflowed) or 0 (overflowed). There is currently a race condition present when disabling and then updating the PMC. Increased NMI latency in newer AMD processors makes this race condition more pronounced. If the counter value has overflowed, it is possible to update the PMC value before the NMI handler can run. The updated PMC value is not an overflowed value, so when the perf NMI handler does run, it will not find an overflowed counter. This may appear as an unknown NMI resulting in either a panic or a series of messages, depending on how the kernel is configured. To eliminate this race condition, the PMC value must be checked after disabling the counter. Add an AMD function, amd_pmu_disable_all(), that will wait for the NMI handler to reset any active and overflowed counter after calling x86_pmu_disable_all(). Signed-off-by: Tom Lendacky <thomas.lendacky@amd.com> Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org> Cc: <stable@vger.kernel.org> # 4.14.x- Cc: Alexander Shishkin <alexander.shishkin@linux.intel.com> Cc: Arnaldo Carvalho de Melo <acme@kernel.org> Cc: Arnaldo Carvalho de Melo <acme@redhat.com> Cc: Borislav Petkov <bp@alien8.de> Cc: Jiri Olsa <jolsa@redhat.com> Cc: Linus Torvalds <torvalds@linux-foundation.org> Cc: Namhyung Kim <namhyung@kernel.org> Cc: Peter Zijlstra <peterz@infradead.org> Cc: Stephane Eranian <eranian@google.com> Cc: Thomas Gleixner <tglx@linutronix.de> Cc: Vince Weaver <vincent.weaver@maine.edu> Link: https://lkml.kernel.org/r/Message-ID: Signed-off-by: Ingo Molnar <mingo@kernel.org>