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2021-08-29Merge tag 'perf_urgent_for_v5.14' of ↵Linus Torvalds
git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip Pull perf fixes from Borislav Petkov: - Prevent the amd/power module from being removed while in use - Mark AMD IBS as not supporting content exclusion - Add a workaround for AMD erratum #1197 where IBS registers might not be restored properly after exiting CC6 state - Fix a potential truncation of a 32-bit variable due to shifting - Read the correct bits describing the number of configurable address ranges on Intel PT * tag 'perf_urgent_for_v5.14' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip: perf/x86/amd/power: Assign pmu.module perf/x86/amd/ibs: Extend PERF_PMU_CAP_NO_EXCLUDE to IBS Op perf/x86/amd/ibs: Work around erratum #1197 perf/x86/intel/uncore: Fix integer overflow on 23 bit left shift of a u32 perf/x86/intel/pt: Fix mask of num_address_ranges
2021-08-29Merge tag 'x86_urgent_for_v5.14' of ↵Linus Torvalds
git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip Pull x86 fixes from Borislav Petkov: - Fix build error on RHEL where -Werror=maybe-uninitialized is set. - Restore the firmware's IDT when calling EFI boot services and before ExitBootServices() has been called. This fixes a boot failure on what appears to be a tablet with 32-bit UEFI running a 64-bit kernel. * tag 'x86_urgent_for_v5.14' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip: x86/resctrl: Fix a maybe-uninitialized build warning treated as error x86/efi: Restore Firmware IDT before calling ExitBootServices()
2021-08-29Revert "parisc: Add assembly implementations for memset, strlen, strcpy, ↵Helge Deller
strncpy and strcat" This reverts commit 83af58f8068ea3f7b3c537c37a30887bfa585069. It turns out that at least the assembly implementation for strncpy() was buggy. Revert the whole commit and return back to the default coding. Signed-off-by: Helge Deller <deller@gmx.de> Cc: <stable@vger.kernel.org> # v5.4+ Cc: Rasmus Villemoes <linux@rasmusvillemoes.dk> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2021-08-28Merge tag 'powerpc-5.14-7' of ↵Linus Torvalds
git://git.kernel.org/pub/scm/linux/kernel/git/powerpc/linux Pull powerpc fixes from Michael Ellerman: - Fix scv implicit soft-mask table for relocated (eg. kdump) kernels - Re-enable ARCH_ENABLE_SPLIT_PMD_PTLOCK, which was disabled due to a typo Thanks to Lukas Bulwahn, Nicholas Piggin, and Daniel Axtens. * tag 'powerpc-5.14-7' of git://git.kernel.org/pub/scm/linux/kernel/git/powerpc/linux: powerpc/64s: Fix scv implicit soft-mask table for relocated kernels powerpc: Re-enable ARCH_ENABLE_SPLIT_PMD_PTLOCK
2021-08-27Merge tag 'riscv-for-linus-5.14-rc8' of ↵Linus Torvalds
git://git.kernel.org/pub/scm/linux/kernel/git/riscv/linux Pull RISC-V fixes from Palmer Dabbelt: - device tree updates for the Microsemi Polarfire development kit that fix some mismatches between the u-boot and Linux enternet entries - ensure that the F register state is correctly reflected in core dumps * tag 'riscv-for-linus-5.14-rc8' of git://git.kernel.org/pub/scm/linux/kernel/git/riscv/linux: riscv: dts: microchip: Add ethernet0 to the aliases node riscv: dts: microchip: Use 'local-mac-address' for emac1 riscv: Ensure the value of FP registers in the core dump file is up to date
2021-08-27Merge tag 'for-linus' of git://git.armlinux.org.uk/~rmk/linux-armLinus Torvalds
Pull ARM fix from Russell King: "Resolve a Keystone 2 kernel mapping regression" * tag 'for-linus' of git://git.armlinux.org.uk/~rmk/linux-arm: ARM: 9104/2: Fix Keystone 2 kernel mapping regression
2021-08-26Merge tag 'arm64-fixes' of ↵Linus Torvalds
git://git.kernel.org/pub/scm/linux/kernel/git/arm64/linux Pull arm64 fix from Will Deacon: "We received a report this week that the generic version of pfn_valid(), which we switched to this merge window in 16c9afc77660 ("arm64/mm: drop HAVE_ARCH_PFN_VALID"), interacts badly with dma_map_resource() due to the following check: /* Don't allow RAM to be mapped */ if (WARN_ON_ONCE(pfn_valid(PHYS_PFN(phys_addr)))) return DMA_MAPPING_ERROR; Since the ongoing saga to determine the semantics of pfn_valid() is unlikely to be resolved this week (does it indicate valid memory, or just the presence of a struct page, or whether that struct page has been initialised?), just revert back to our old version of pfn_valid() for 5.14. Summary: - Fix dma_map_resource() by reverting back to old pfn_valid() code" * tag 'arm64-fixes' of git://git.kernel.org/pub/scm/linux/kernel/git/arm64/linux: Partially revert "arm64/mm: drop HAVE_ARCH_PFN_VALID"
2021-08-26perf/x86/amd/power: Assign pmu.moduleKim Phillips
Assign pmu.module so the driver can't be unloaded whilst in use. Signed-off-by: Kim Phillips <kim.phillips@amd.com> Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org> Signed-off-by: Ingo Molnar <mingo@kernel.org> Link: https://lore.kernel.org/r/20210817221048.88063-4-kim.phillips@amd.com
2021-08-26perf/x86/amd/ibs: Extend PERF_PMU_CAP_NO_EXCLUDE to IBS OpKim Phillips
Commit: 2ff40250691e ("perf/core, arch/x86: Use PERF_PMU_CAP_NO_EXCLUDE for exclusion incapable PMUs") neglected to do so. Fixes: 2ff40250691e ("perf/core, arch/x86: Use PERF_PMU_CAP_NO_EXCLUDE for exclusion incapable PMUs") Signed-off-by: Kim Phillips <kim.phillips@amd.com> Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org> Signed-off-by: Ingo Molnar <mingo@kernel.org> Cc: stable@vger.kernel.org Link: https://lore.kernel.org/r/20210817221048.88063-2-kim.phillips@amd.com
2021-08-26perf/x86/amd/ibs: Work around erratum #1197Kim Phillips
Erratum #1197 "IBS (Instruction Based Sampling) Register State May be Incorrect After Restore From CC6" is published in a document: "Revision Guide for AMD Family 19h Models 00h-0Fh Processors" 56683 Rev. 1.04 July 2021 https://bugzilla.kernel.org/show_bug.cgi?id=206537 Implement the erratum's suggested workaround and ignore IBS samples if MSRC001_1031 == 0. Signed-off-by: Kim Phillips <kim.phillips@amd.com> Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org> Signed-off-by: Ingo Molnar <mingo@kernel.org> Link: https://lore.kernel.org/r/20210817221048.88063-3-kim.phillips@amd.com
2021-08-26perf/x86/intel/uncore: Fix integer overflow on 23 bit left shift of a u32Colin Ian King
The u32 variable pci_dword is being masked with 0x1fffffff and then left shifted 23 places. The shift is a u32 operation,so a value of 0x200 or more in pci_dword will overflow the u32 and only the bottow 32 bits are assigned to addr. I don't believe this was the original intent. Fix this by casting pci_dword to a resource_size_t to ensure no overflow occurs. Note that the mask and 12 bit left shift operation does not need this because the mask SNR_IMC_MMIO_MEM0_MASK and shift is always a 32 bit value. Fixes: ee49532b38dd ("perf/x86/intel/uncore: Add IMC uncore support for Snow Ridge") Addresses-Coverity: ("Unintentional integer overflow") Signed-off-by: Colin Ian King <colin.king@canonical.com> Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org> Signed-off-by: Ingo Molnar <mingo@kernel.org> Reviewed-by: Kan Liang <kan.liang@linux.intel.com> Link: https://lore.kernel.org/r/20210706114553.28249-1-colin.king@canonical.com
2021-08-25perf/x86/intel/pt: Fix mask of num_address_rangesXiaoyao Li
Per SDM, bit 2:0 of CPUID(0x14,1).EAX[2:0] reports the number of configurable address ranges for filtering, not bit 1:0. Signed-off-by: Xiaoyao Li <xiaoyao.li@intel.com> Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org> Acked-by: Alexander Shishkin <alexander.shishkin@linux.intel.com> Link: https://lkml.kernel.org/r/20210824040622.4081502-1-xiaoyao.li@intel.com
2021-08-25Partially revert "arm64/mm: drop HAVE_ARCH_PFN_VALID"Will Deacon
This partially reverts commit 16c9afc776608324ca71c0bc354987bab532f51d. Alex Bee reports a regression in 5.14 on their RK3328 SoC when configuring the PL330 DMA controller: | ------------[ cut here ]------------ | WARNING: CPU: 2 PID: 373 at kernel/dma/mapping.c:235 dma_map_resource+0x68/0xc0 | Modules linked in: spi_rockchip(+) fuse | CPU: 2 PID: 373 Comm: systemd-udevd Not tainted 5.14.0-rc7 #1 | Hardware name: Pine64 Rock64 (DT) | pstate: 80000005 (Nzcv daif -PAN -UAO -TCO BTYPE=--) | pc : dma_map_resource+0x68/0xc0 | lr : pl330_prep_slave_fifo+0x78/0xd0 This appears to be because dma_map_resource() is being called for a physical address which does not correspond to a memory address yet does have a valid 'struct page' due to the way in which the vmemmap is constructed. Prior to 16c9afc77660 ("arm64/mm: drop HAVE_ARCH_PFN_VALID"), the arm64 implementation of pfn_valid() called memblock_is_memory() to return 'false' for such regions and the DMA mapping request would proceed. However, now that we are using the generic implementation where only the presence of the memory map entry is considered, we return 'true' and erroneously fail with DMA_MAPPING_ERROR because we identify the region as DRAM. Although fixing this in the DMA mapping code is arguably the right fix, it is a risky, cross-architecture change at this stage in the cycle. So just revert arm64 back to its old pfn_valid() implementation for v5.14. The change to the generic pfn_valid() code is preserved from the original patch, so as to avoid impacting other architectures. Cc: Catalin Marinas <catalin.marinas@arm.com> Cc: Robin Murphy <robin.murphy@arm.com> Cc: Mike Rapoport <rppt@kernel.org> Cc: Anshuman Khandual <anshuman.khandual@arm.com> Cc: Christoph Hellwig <hch@lst.de> Reported-by: Alex Bee <knaerzche@gmail.com> Link: https://lore.kernel.org/r/d3a3c828-b777-faf8-e901-904995688437@gmail.com Signed-off-by: Will Deacon <will@kernel.org>
2021-08-24riscv: dts: microchip: Add ethernet0 to the aliases nodeBin Meng
U-Boot expects this alias to be in place in order to fix up the mac address of the ethernet node. Note on the Icicle Kit board, currently only emac1 is enabled so it becomes the 'ethernet0'. Signed-off-by: Bin Meng <bin.meng@windriver.com> Reviewed-by: Geert Uytterhoeven <geert@linux-m68k.org> Signed-off-by: Palmer Dabbelt <palmerdabbelt@google.com>
2021-08-24riscv: dts: microchip: Use 'local-mac-address' for emac1Bin Meng
Per the DT spec, 'local-mac-address' is used to specify MAC address that was assigned to the network device, while 'mac-address' is used to specify the MAC address that was last used by the boot program, and shall be used only if the value differs from 'local-mac-address' property value. Signed-off-by: Bin Meng <bin.meng@windriver.com> Reviewed-by: conor dooley <conor.dooley@microchip.com> Reviewed-by: Geert Uytterhoeven <geert@linux-m68k.org> Signed-off-by: Palmer Dabbelt <palmerdabbelt@google.com>
2021-08-24riscv: Ensure the value of FP registers in the core dump file is up to dateVincent Chen
The value of FP registers in the core dump file comes from the thread.fstate. However, kernel saves the FP registers to the thread.fstate only before scheduling out the process. If no process switch happens during the exception handling process, kernel will not have a chance to save the latest value of FP registers to thread.fstate. It will cause the value of FP registers in the core dump file may be incorrect. To solve this problem, this patch force lets kernel save the FP register into the thread.fstate if the target task_struct equals the current. Signed-off-by: Vincent Chen <vincent.chen@sifive.com> Reviewed-by: Jisheng Zhang <jszhang@kernel.org> Fixes: b8c8a9590e4f ("RISC-V: Add FP register ptrace support for gdb.") Cc: stable@vger.kernel.org Signed-off-by: Palmer Dabbelt <palmerdabbelt@google.com>
2021-08-22Merge tag 'powerpc-5.14-6' of ↵Linus Torvalds
git://git.kernel.org/pub/scm/linux/kernel/git/powerpc/linux Pull powerpc fixes from Michael Ellerman: - Fix random crashes on some 32-bit CPUs by adding isync() after locking/unlocking KUEP - Fix intermittent crashes when loading modules with strict module RWX - Fix a section mismatch introduce by a previous fix. Thanks to Christophe Leroy, Fabiano Rosas, Laurent Vivier, Murilo Opsfelder Araújo, Nathan Chancellor, and Stan Johnson. h# -----BEGIN PGP SIGNATURE----- * tag 'powerpc-5.14-6' of git://git.kernel.org/pub/scm/linux/kernel/git/powerpc/linux: powerpc/mm: Fix set_memory_*() against concurrent accesses powerpc/32s: Fix random crashes by adding isync() after locking/unlocking KUEP powerpc/xive: Do not mark xive_request_ipi() as __init
2021-08-22x86/resctrl: Fix a maybe-uninitialized build warning treated as errorBabu Moger
The recent commit 064855a69003 ("x86/resctrl: Fix default monitoring groups reporting") caused a RHEL build failure with an uninitialized variable warning treated as an error because it removed the default case snippet. The RHEL Makefile uses '-Werror=maybe-uninitialized' to force possibly uninitialized variable warnings to be treated as errors. This is also reported by smatch via the 0day robot. The error from the RHEL build is: arch/x86/kernel/cpu/resctrl/monitor.c: In function ‘__mon_event_count’: arch/x86/kernel/cpu/resctrl/monitor.c:261:12: error: ‘m’ may be used uninitialized in this function [-Werror=maybe-uninitialized] m->chunks += chunks; ^~ The upstream Makefile does not build using '-Werror=maybe-uninitialized'. So, the problem is not seen there. Fix the problem by putting back the default case snippet. [ bp: note that there's nothing wrong with the code and other compilers do not trigger this warning - this is being done just so the RHEL compiler is happy. ] Fixes: 064855a69003 ("x86/resctrl: Fix default monitoring groups reporting") Reported-by: Terry Bowman <Terry.Bowman@amd.com> Reported-by: kernel test robot <lkp@intel.com> Signed-off-by: Babu Moger <babu.moger@amd.com> Signed-off-by: Borislav Petkov <bp@suse.de> Reviewed-by: Reinette Chatre <reinette.chatre@intel.com> Cc: stable@vger.kernel.org Link: https://lkml.kernel.org/r/162949631908.23903.17090272726012848523.stgit@bmoger-ubuntu
2021-08-21Merge tag 'riscv-for-linus-5.14-rc7' of ↵Linus Torvalds
git://git.kernel.org/pub/scm/linux/kernel/git/riscv/linux Pull RISC-V fixes from Palmer Dabbelt: - fix the sifive-l2-cache device tree bindings for json-schema compatibility. This does not change the intended behavior of the binding. - avoid improperly freeing necessary resources during early boot. * tag 'riscv-for-linus-5.14-rc7' of git://git.kernel.org/pub/scm/linux/kernel/git/riscv/linux: riscv: Fix a number of free'd resources in init_resources() dt-bindings: sifive-l2-cache: Fix 'select' matching
2021-08-21Merge tag 's390-5.14-5' of ↵Linus Torvalds
git://git.kernel.org/pub/scm/linux/kernel/git/s390/linux Pull s390 fix from Vasily Gorbik: - fix use after free of zpci_dev in pci code * tag 's390-5.14-5' of git://git.kernel.org/pub/scm/linux/kernel/git/s390/linux: s390/pci: fix use after free of zpci_dev
2021-08-21x86/efi: Restore Firmware IDT before calling ExitBootServices()Joerg Roedel
Commit 79419e13e808 ("x86/boot/compressed/64: Setup IDT in startup_32 boot path") introduced an IDT into the 32-bit boot path of the decompressor stub. But the IDT is set up before ExitBootServices() is called, and some UEFI firmwares rely on their own IDT. Save the firmware IDT on boot and restore it before calling into EFI functions to fix boot failures introduced by above commit. Fixes: 79419e13e808 ("x86/boot/compressed/64: Setup IDT in startup_32 boot path") Reported-by: Fabio Aiuto <fabioaiuto83@gmail.com> Signed-off-by: Joerg Roedel <jroedel@suse.de> Signed-off-by: Borislav Petkov <bp@suse.de> Acked-by: Ard Biesheuvel <ardb@kernel.org> Cc: stable@vger.kernel.org # 5.13+ Link: https://lkml.kernel.org/r/20210820125703.32410-1-joro@8bytes.org
2021-08-20Merge tag 'arm64-fixes' of ↵Linus Torvalds
git://git.kernel.org/pub/scm/linux/kernel/git/arm64/linux Pull arm64 fixes from Will Deacon: - Fix cleaning of vDSO directories - Ensure CNTHCTL_EL2 is fully initialised when booting at EL2 * tag 'arm64-fixes' of git://git.kernel.org/pub/scm/linux/kernel/git/arm64/linux: arm64: initialize all of CNTHCTL_EL2 arm64: clean vdso & vdso32 files
2021-08-20riscv: Fix a number of free'd resources in init_resources()Petr Pavlu
Function init_resources() allocates a boot memory block to hold an array of resources which it adds to iomem_resource. The array is filled in from its end and the function then attempts to free any unused memory at the beginning. The problem is that size of the unused memory is incorrectly calculated and this can result in releasing memory which is in use by active resources. Their data then gets corrupted later when the memory is reused by a different part of the system. Fix the size of the released memory to correctly match the number of unused resource entries. Fixes: ffe0e5261268 ("RISC-V: Improve init_resources()") Signed-off-by: Petr Pavlu <petr.pavlu@suse.com> Reviewed-by: Sunil V L <sunilvl@ventanamicro.com> Acked-by: Nick Kossifidis <mick@ics.forth.gr> Tested-by: Sunil V L <sunilvl@ventanamicro.com> Cc: stable@vger.kernel.org Signed-off-by: Palmer Dabbelt <palmerdabbelt@google.com>
2021-08-20powerpc/64s: Fix scv implicit soft-mask table for relocated kernelsNicholas Piggin
The implict soft-mask table addresses get relocated if they use a relative symbol like a label. This is right for code that runs relocated but not for unrelocated. The scv interrupt vectors run unrelocated, so absolute addresses are required for their soft-mask table entry. This fixes crashing with relocated kernels, usually an asynchronous interrupt hitting in the scv handler, then hitting the trap that checks whether r1 is in userspace. Fixes: 325678fd0522 ("powerpc/64s: add a table of implicit soft-masked addresses") Signed-off-by: Nicholas Piggin <npiggin@gmail.com> Signed-off-by: Michael Ellerman <mpe@ellerman.id.au> Link: https://lore.kernel.org/r/20210820103431.1701240-1-npiggin@gmail.com
2021-08-20powerpc: Re-enable ARCH_ENABLE_SPLIT_PMD_PTLOCKLukas Bulwahn
Commit 66f24fa766e3 ("mm: drop redundant ARCH_ENABLE_SPLIT_PMD_PTLOCK") broke PMD split page table lock for powerpc. It selects the non-existent config ARCH_ENABLE_PMD_SPLIT_PTLOCK in arch/powerpc/platforms/Kconfig.cputype, but clearly intended to select ARCH_ENABLE_SPLIT_PMD_PTLOCK (notice the word swapping!), as that commit did for all other architectures. Fix it by selecting the correct symbol ARCH_ENABLE_SPLIT_PMD_PTLOCK. Fixes: 66f24fa766e3 ("mm: drop redundant ARCH_ENABLE_SPLIT_PMD_PTLOCK") Cc: stable@vger.kernel.org # v5.13+ Signed-off-by: Lukas Bulwahn <lukas.bulwahn@gmail.com> Reviewed-by: Daniel Axtens <dja@axtens.net> [mpe: Reword change log to make it clear this is a bug fix] Signed-off-by: Michael Ellerman <mpe@ellerman.id.au> Link: https://lore.kernel.org/r/20210819113954.17515-3-lukas.bulwahn@gmail.com
2021-08-19Merge tag 'soc-fixes-5.14-3' of ↵Linus Torvalds
git://git.kernel.org/pub/scm/linux/kernel/git/soc/soc Pull ARM SoC fixes from Arnd Bergmann: "Not much to see here. Half the fixes this time are for Qualcomm dts files, fixing small mistakes on certain machines. The other fixes are: - A 5.13 regression fix for freescale QE interrupt controller\ - A fix for TI OMAP gpt12 timer error handling - A randconfig build regression fix for ixp4xx - Another defconfig fix following the CONFIG_FB dependency rework" * tag 'soc-fixes-5.14-3' of git://git.kernel.org/pub/scm/linux/kernel/git/soc/soc: soc: fsl: qe: fix static checker warning ARM: ixp4xx: fix building both pci drivers ARM: configs: Update the nhk8815_defconfig bus: ti-sysc: Fix error handling for sysc_check_active_timer() soc: fsl: qe: convert QE interrupt controller to platform_device arm64: dts: qcom: sdm845-oneplus: fix reserved-mem arm64: dts: qcom: msm8994-angler: Disable cont_splash_mem arm64: dts: qcom: sc7280: Fixup cpufreq domain info for cpu7 arm64: dts: qcom: msm8992-bullhead: Fix cont_splash_mem mapping arm64: dts: qcom: msm8992-bullhead: Remove PSCI arm64: dts: qcom: c630: fix correct powerdown pin for WSA881x
2021-08-19arm64: initialize all of CNTHCTL_EL2Mark Rutland
In __init_el2_timers we initialize CNTHCTL_EL2.{EL1PCEN,EL1PCTEN} with a RMW sequence, leaving all other bits UNKNOWN. In general, we should initialize all bits in a register rather than using an RMW sequence, since most bits are UNKNOWN out of reset, and as new bits are added to the reigster their reset value might not result in expected behaviour. In the case of CNTHCTL_EL2, FEAT_ECV added a number of new control bits in previously RES0 bits, which reset to UNKNOWN values, and may cause issues for EL1 and EL0: * CNTHCTL_EL2.ECV enables the CNTPOFF_EL2 offset (which itself resets to an UNKNOWN value) at EL0 and EL1. Since the offset could reset to distinct values across CPUs, when the control bit resets to 1 this could break timekeeping generally. * CNTHCTL_EL2.{EL1TVT,EL1TVCT} trap EL0 and EL1 accesses to the EL1 virtual timer/counter registers to EL2. When reset to 1, this could cause unexpected traps to EL2. Initializing these bits to zero avoids these problems, and all other bits in CNTHCTL_EL2 other than EL1PCEN and EL1PCTEN can safely be reset to zero. This patch ensures we initialize CNTHCTL_EL2 accordingly, only setting EL1PCEN and EL1PCTEN, and setting all other bits to zero. Signed-off-by: Mark Rutland <mark.rutland@arm.com> Cc: Catalin Marinas <catalin.marinas@arm.com> Cc: Marc Zyngier <maz@kernel.org> Cc: Oliver Upton <oupton@google.com> Cc: Will Deacon <will@kernel.org> Reviewed-by: Oliver Upton <oupton@google.com> Acked-by: Marc Zyngier <maz@kernel.org> Link: https://lore.kernel.org/r/20210818161535.52786-1-mark.rutland@arm.com Signed-off-by: Will Deacon <will@kernel.org>
2021-08-19powerpc/mm: Fix set_memory_*() against concurrent accessesMichael Ellerman
Laurent reported that STRICT_MODULE_RWX was causing intermittent crashes on one of his systems: kernel tried to execute exec-protected page (c008000004073278) - exploit attempt? (uid: 0) BUG: Unable to handle kernel instruction fetch Faulting instruction address: 0xc008000004073278 Oops: Kernel access of bad area, sig: 11 [#1] LE PAGE_SIZE=64K MMU=Radix SMP NR_CPUS=2048 NUMA pSeries Modules linked in: drm virtio_console fuse drm_panel_orientation_quirks ... CPU: 3 PID: 44 Comm: kworker/3:1 Not tainted 5.14.0-rc4+ #12 Workqueue: events control_work_handler [virtio_console] NIP: c008000004073278 LR: c008000004073278 CTR: c0000000001e9de0 REGS: c00000002e4ef7e0 TRAP: 0400 Not tainted (5.14.0-rc4+) MSR: 800000004280b033 <SF,VEC,VSX,EE,FP,ME,IR,DR,RI,LE> CR: 24002822 XER: 200400cf ... NIP fill_queue+0xf0/0x210 [virtio_console] LR fill_queue+0xf0/0x210 [virtio_console] Call Trace: fill_queue+0xb4/0x210 [virtio_console] (unreliable) add_port+0x1a8/0x470 [virtio_console] control_work_handler+0xbc/0x1e8 [virtio_console] process_one_work+0x290/0x590 worker_thread+0x88/0x620 kthread+0x194/0x1a0 ret_from_kernel_thread+0x5c/0x64 Jordan, Fabiano & Murilo were able to reproduce and identify that the problem is caused by the call to module_enable_ro() in do_init_module(), which happens after the module's init function has already been called. Our current implementation of change_page_attr() is not safe against concurrent accesses, because it invalidates the PTE before flushing the TLB and then installing the new PTE. That leaves a window in time where there is no valid PTE for the page, if another CPU tries to access the page at that time we see something like the fault above. We can't simply switch to set_pte_at()/flush TLB, because our hash MMU code doesn't handle a set_pte_at() of a valid PTE. See [1]. But we do have pte_update(), which replaces the old PTE with the new, meaning there's no window where the PTE is invalid. And the hash MMU version hash__pte_update() deals with synchronising the hash page table correctly. [1]: https://lore.kernel.org/linuxppc-dev/87y318wp9r.fsf@linux.ibm.com/ Fixes: 1f9ad21c3b38 ("powerpc/mm: Implement set_memory() routines") Reported-by: Laurent Vivier <lvivier@redhat.com> Reviewed-by: Christophe Leroy <christophe.leroy@csgroup.eu> Reviewed-by: Murilo Opsfelder Araújo <muriloo@linux.ibm.com> Tested-by: Laurent Vivier <lvivier@redhat.com> Signed-off-by: Fabiano Rosas <farosas@linux.ibm.com> Signed-off-by: Michael Ellerman <mpe@ellerman.id.au> Link: https://lore.kernel.org/r/20210818120518.3603172-1-mpe@ellerman.id.au
2021-08-19powerpc/32s: Fix random crashes by adding isync() after locking/unlocking KUEPChristophe Leroy
Commit b5efec00b671 ("powerpc/32s: Move KUEP locking/unlocking in C") removed the 'isync' instruction after adding/removing NX bit in user segments. The reasoning behind this change was that when setting the NX bit we don't mind it taking effect with delay as the kernel never executes text from userspace, and when clearing the NX bit this is to return to userspace and then the 'rfi' should synchronise the context. However, it looks like on book3s/32 having a hash page table, at least on the G3 processor, we get an unexpected fault from userspace, then this is followed by something wrong in the verification of MSR_PR at end of another interrupt. This is fixed by adding back the removed isync() following update of NX bit in user segment registers. Only do it for cores with an hash table, as 603 cores don't exhibit that problem and the two isync increase ./null_syscall selftest by 6 cycles on an MPC 832x. First problem: unexpected WARN_ON() for mysterious PROTFAULT WARNING: CPU: 0 PID: 1660 at arch/powerpc/mm/fault.c:354 do_page_fault+0x6c/0x5b0 Modules linked in: CPU: 0 PID: 1660 Comm: Xorg Not tainted 5.13.0-pmac-00028-gb3c15b60339a #40 NIP: c001b5c8 LR: c001b6f8 CTR: 00000000 REGS: e2d09e40 TRAP: 0700 Not tainted (5.13.0-pmac-00028-gb3c15b60339a) MSR: 00021032 <ME,IR,DR,RI> CR: 42d04f30 XER: 20000000 GPR00: c000424c e2d09f00 c301b680 e2d09f40 0000001e 42000000 00cba028 00000000 GPR08: 08000000 48000010 c301b680 e2d09f30 22d09f30 00c1fff0 00cba000 a7b7ba4c GPR16: 00000031 00000000 00000000 00000000 00000000 00000000 a7b7b0d0 00c5c010 GPR24: a7b7b64c a7b7d2f0 00000004 00000000 c1efa6c0 00cba02c 00000300 e2d09f40 NIP [c001b5c8] do_page_fault+0x6c/0x5b0 LR [c001b6f8] do_page_fault+0x19c/0x5b0 Call Trace: [e2d09f00] [e2d09f04] 0xe2d09f04 (unreliable) [e2d09f30] [c000424c] DataAccess_virt+0xd4/0xe4 --- interrupt: 300 at 0xa7a261dc NIP: a7a261dc LR: a7a253bc CTR: 00000000 REGS: e2d09f40 TRAP: 0300 Not tainted (5.13.0-pmac-00028-gb3c15b60339a) MSR: 0000d032 <EE,PR,ME,IR,DR,RI> CR: 228428e2 XER: 20000000 DAR: 00cba02c DSISR: 42000000 GPR00: a7a27448 afa6b0e0 a74c35c0 a7b7b614 0000001e a7b7b614 00cba028 00000000 GPR08: 00020fd9 00000031 00cb9ff8 a7a273b0 220028e2 00c1fff0 00cba000 a7b7ba4c GPR16: 00000031 00000000 00000000 00000000 00000000 00000000 a7b7b0d0 00c5c010 GPR24: a7b7b64c a7b7d2f0 00000004 00000002 0000001e a7b7b614 a7b7aff4 00000030 NIP [a7a261dc] 0xa7a261dc LR [a7a253bc] 0xa7a253bc --- interrupt: 300 Instruction dump: 7c4a1378 810300a0 75278410 83820298 83a300a4 553b018c 551e0036 4082038c 2e1b0000 40920228 75280800 41820220 <0fe00000> 3b600000 41920214 81420594 Second problem: MSR PR is seen unset allthough the interrupt frame shows it set kernel BUG at arch/powerpc/kernel/interrupt.c:458! Oops: Exception in kernel mode, sig: 5 [#1] BE PAGE_SIZE=4K MMU=Hash SMP NR_CPUS=2 PowerMac Modules linked in: CPU: 0 PID: 1660 Comm: Xorg Tainted: G W 5.13.0-pmac-00028-gb3c15b60339a #40 NIP: c0011434 LR: c001629c CTR: 00000000 REGS: e2d09e70 TRAP: 0700 Tainted: G W (5.13.0-pmac-00028-gb3c15b60339a) MSR: 00029032 <EE,ME,IR,DR,RI> CR: 42d09f30 XER: 00000000 GPR00: 00000000 e2d09f30 c301b680 e2d09f40 83440000 c44d0e68 e2d09e8c 00000000 GPR08: 00000002 00dc228a 00004000 e2d09f30 22d09f30 00c1fff0 afa6ceb4 00c26144 GPR16: 00c25fb8 00c26140 afa6ceb8 90000000 00c944d8 0000001c 00000000 00200000 GPR24: 00000000 000001fb afa6d1b4 00000001 00000000 a539a2a0 a530fd80 00000089 NIP [c0011434] interrupt_exit_kernel_prepare+0x10/0x70 LR [c001629c] interrupt_return+0x9c/0x144 Call Trace: [e2d09f30] [c000424c] DataAccess_virt+0xd4/0xe4 (unreliable) --- interrupt: 300 at 0xa09be008 NIP: a09be008 LR: a09bdfe8 CTR: a09bdfc0 REGS: e2d09f40 TRAP: 0300 Tainted: G W (5.13.0-pmac-00028-gb3c15b60339a) MSR: 0000d032 <EE,PR,ME,IR,DR,RI> CR: 420028e2 XER: 20000000 DAR: a539a308 DSISR: 0a000000 GPR00: a7b90d50 afa6b2d0 a74c35c0 a0a8b690 a0a8b698 a5365d70 a4fa82a8 00000004 GPR08: 00000000 a09bdfc0 00000000 a5360000 a09bde7c 00c1fff0 afa6ceb4 00c26144 GPR16: 00c25fb8 00c26140 afa6ceb8 90000000 00c944d8 0000001c 00000000 00200000 GPR24: 00000000 000001fb afa6d1b4 00000001 00000000 a539a2a0 a530fd80 00000089 NIP [a09be008] 0xa09be008 LR [a09bdfe8] 0xa09bdfe8 --- interrupt: 300 Instruction dump: 80010024 83e1001c 7c0803a6 4bffff80 3bc00800 4bffffd0 486b42fd 4bffffcc 81430084 71480002 41820038 554a0462 <0f0a0000> 80620060 74630001 40820034 Fixes: b5efec00b671 ("powerpc/32s: Move KUEP locking/unlocking in C") Cc: stable@vger.kernel.org # v5.13+ Reported-by: Stan Johnson <userm57@yahoo.com> Signed-off-by: Christophe Leroy <christophe.leroy@csgroup.eu> Signed-off-by: Michael Ellerman <mpe@ellerman.id.au> Link: https://lore.kernel.org/r/4856f5574906e2aec0522be17bf3848a22b2cd0b.1629269345.git.christophe.leroy@csgroup.eu
2021-08-18powerpc/xive: Do not mark xive_request_ipi() as __initNathan Chancellor
Compiling ppc64le_defconfig with clang-14 shows a modpost warning: WARNING: modpost: vmlinux.o(.text+0xa74e0): Section mismatch in reference from the function xive_setup_cpu_ipi() to the function .init.text:xive_request_ipi() The function xive_setup_cpu_ipi() references the function __init xive_request_ipi(). This is often because xive_setup_cpu_ipi lacks a __init annotation or the annotation of xive_request_ipi is wrong. xive_request_ipi() is called from xive_setup_cpu_ipi(), which is not __init, so xive_request_ipi() should not be marked __init. Remove the attribute so there is no more warning. Fixes: cbc06f051c52 ("powerpc/xive: Do not skip CPU-less nodes when creating the IPIs") Signed-off-by: Nathan Chancellor <nathan@kernel.org> Reviewed-by: Nick Desaulniers <ndesaulniers@google.com> Signed-off-by: Michael Ellerman <mpe@ellerman.id.au> Link: https://lore.kernel.org/r/20210816185711.21563-1-nathan@kernel.org
2021-08-18s390/pci: fix use after free of zpci_devNiklas Schnelle
The struct pci_dev uses reference counting but zPCI assumed erroneously that the last reference would always be the local reference after calling pci_stop_and_remove_bus_device(). This is usually the case but not how reference counting works and thus inherently fragile. In fact one case where this causes a NULL pointer dereference when on an SRIOV device the function 0 was hot unplugged before another function of the same multi-function device. In this case the second function's pdev->sriov->dev reference keeps the struct pci_dev of function 0 alive even after the unplug. This bug was previously hidden by the fact that we were leaking the struct pci_dev which in turn means that it always outlived the struct zpci_dev. This was fixed in commit 0b13525c20fe ("s390/pci: fix leak of PCI device structure") exposing the broken behavior. Fix this by accounting for the long living reference a struct pci_dev has to its underlying struct zpci_dev via the zbus->function[] array and only release that in pcibios_release_device() ensuring that the struct pci_dev is not left with a dangling reference. This is a minimal fix in the future it would probably better to use fine grained reference counting for struct zpci_dev. Fixes: 05bc1be6db4b2 ("s390/pci: create zPCI bus") Cc: stable@vger.kernel.org Reviewed-by: Matthew Rosato <mjrosato@linux.ibm.com> Signed-off-by: Niklas Schnelle <schnelle@linux.ibm.com> Signed-off-by: Vasily Gorbik <gor@linux.ibm.com>
2021-08-16Merge tag 'qcom-arm64-fixes-for-5.14' of ↵Arnd Bergmann
git://git.kernel.org/pub/scm/linux/kernel/git/qcom/linux into arm/fixes Qualcomm ARM64 fixes for v5.14 This fixes three regressions across Angler and Bullhead, introduced by advancements in the platform definition. It then corrects the powerdown GPIOs for the speaker amps on C630 and lastly fixes a typo that assigned CPU7 in SC7280 to the wrong CPUfreq domain. * tag 'qcom-arm64-fixes-for-5.14' of git://git.kernel.org/pub/scm/linux/kernel/git/qcom/linux: arm64: dts: qcom: sdm845-oneplus: fix reserved-mem arm64: dts: qcom: msm8994-angler: Disable cont_splash_mem arm64: dts: qcom: sc7280: Fixup cpufreq domain info for cpu7 arm64: dts: qcom: msm8992-bullhead: Fix cont_splash_mem mapping arm64: dts: qcom: msm8992-bullhead: Remove PSCI arm64: dts: qcom: c630: fix correct powerdown pin for WSA881x Link: https://lore.kernel.org/r/20210816205030.576348-1-bjorn.andersson@linaro.org Signed-off-by: Arnd Bergmann <arnd@arndb.de>
2021-08-16Merge tag 'for-linus' of git://git.kernel.org/pub/scm/virt/kvm/kvmLinus Torvalds
Pull KVM fixes from Paolo Bonzini: "Two nested virtualization fixes for AMD processors" * tag 'for-linus' of git://git.kernel.org/pub/scm/virt/kvm/kvm: KVM: nSVM: always intercept VMLOAD/VMSAVE when nested (CVE-2021-3656) KVM: nSVM: avoid picking up unsupported bits from L2 in int_ctl (CVE-2021-3653)
2021-08-16KVM: nSVM: always intercept VMLOAD/VMSAVE when nested (CVE-2021-3656)Maxim Levitsky
If L1 disables VMLOAD/VMSAVE intercepts, and doesn't enable Virtual VMLOAD/VMSAVE (currently not supported for the nested hypervisor), then VMLOAD/VMSAVE must operate on the L1 physical memory, which is only possible by making L0 intercept these instructions. Failure to do so allowed the nested guest to run VMLOAD/VMSAVE unintercepted, and thus read/write portions of the host physical memory. Fixes: 89c8a4984fc9 ("KVM: SVM: Enable Virtual VMLOAD VMSAVE feature") Suggested-by: Paolo Bonzini <pbonzini@redhat.com> Signed-off-by: Maxim Levitsky <mlevitsk@redhat.com> Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
2021-08-16KVM: nSVM: avoid picking up unsupported bits from L2 in int_ctl (CVE-2021-3653)Maxim Levitsky
* Invert the mask of bits that we pick from L2 in nested_vmcb02_prepare_control * Invert and explicitly use VIRQ related bits bitmask in svm_clear_vintr This fixes a security issue that allowed a malicious L1 to run L2 with AVIC enabled, which allowed the L2 to exploit the uninitialized and enabled AVIC to read/write the host physical memory at some offsets. Fixes: 3d6368ef580a ("KVM: SVM: Add VMRUN handler") Signed-off-by: Maxim Levitsky <mlevitsk@redhat.com> Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
2021-08-15Merge tag 'powerpc-5.14-5' of ↵Linus Torvalds
git://git.kernel.org/pub/scm/linux/kernel/git/powerpc/linux Pull powerpc fixes from Michael Ellerman: - Fix crashes coming out of nap on 32-bit Book3s (eg. powerbooks). - Fix critical and debug interrupts on BookE, seen as crashes when using ptrace. - Fix an oops when running an SMP kernel on a UP system. - Update pseries LPAR security flavor after partition migration. - Fix an oops when using kprobes on BookE. - Fix oops on 32-bit pmac by not calling do_IRQ() from timer_interrupt(). - Fix softlockups on CPU hotplug into a CPU-less node with xive (P9). Thanks to Cédric Le Goater, Christophe Leroy, Finn Thain, Geetika Moolchandani, Laurent Dufour, Laurent Vivier, Nicholas Piggin, Pu Lehui, Radu Rendec, Srikar Dronamraju, and Stan Johnson. * tag 'powerpc-5.14-5' of git://git.kernel.org/pub/scm/linux/kernel/git/powerpc/linux: powerpc/xive: Do not skip CPU-less nodes when creating the IPIs powerpc/interrupt: Do not call single_step_exception() from other exceptions powerpc/interrupt: Fix OOPS by not calling do_IRQ() from timer_interrupt() powerpc/kprobes: Fix kprobe Oops happens in booke powerpc/pseries: Fix update of LPAR security flavor after LPM powerpc/smp: Fix OOPS in topology_init() powerpc/32: Fix critical and debug interrupts on BOOKE powerpc/32s: Fix napping restore in data storage interrupt (DSI)
2021-08-15Merge tag 'irq-urgent-2021-08-15' of ↵Linus Torvalds
git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip Pull irq fixes from Thomas Gleixner: "A set of fixes for PCI/MSI and x86 interrupt startup: - Mask all MSI-X entries when enabling MSI-X otherwise stale unmasked entries stay around e.g. when a crashkernel is booted. - Enforce masking of a MSI-X table entry when updating it, which mandatory according to speification - Ensure that writes to MSI[-X} tables are flushed. - Prevent invalid bits being set in the MSI mask register - Properly serialize modifications to the mask cache and the mask register for multi-MSI. - Cure the violation of the affinity setting rules on X86 during interrupt startup which can cause lost and stale interrupts. Move the initial affinity setting ahead of actualy enabling the interrupt. - Ensure that MSI interrupts are completely torn down before freeing them in the error handling case. - Prevent an array out of bounds access in the irq timings code" * tag 'irq-urgent-2021-08-15' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip: driver core: Add missing kernel doc for device::msi_lock genirq/msi: Ensure deactivation on teardown genirq/timings: Prevent potential array overflow in __irq_timings_store() x86/msi: Force affinity setup before startup x86/ioapic: Force affinity setup before startup genirq: Provide IRQCHIP_AFFINITY_PRE_STARTUP PCI/MSI: Protect msi_desc::masked for multi-MSI PCI/MSI: Use msi_mask_irq() in pci_msi_shutdown() PCI/MSI: Correct misleading comments PCI/MSI: Do not set invalid bits in MSI mask PCI/MSI: Enforce MSI[X] entry updates to be visible PCI/MSI: Enforce that MSI-X table entry is masked for update PCI/MSI: Mask all unused MSI-X entries PCI/MSI: Enable and mask MSI-X early
2021-08-15Merge tag 'x86_urgent_for_v5.14_rc6' of ↵Linus Torvalds
git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip Pull x86 fixes from Borislav Petkov: "Two fixes: - An objdump checker fix to ignore parenthesized strings in the objdump version - Fix resctrl default monitoring groups reporting when new subgroups get created" * tag 'x86_urgent_for_v5.14_rc6' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip: x86/resctrl: Fix default monitoring groups reporting x86/tools: Fix objdump version check again
2021-08-15Merge tag 'for-linus' of git://git.kernel.org/pub/scm/virt/kvm/kvmLinus Torvalds
Pull KVM fixes from Paolo Bonzini: "ARM: - Plug race between enabling MTE and creating vcpus - Fix off-by-one bug when checking whether an address range is RAM x86: - Fixes for the new MMU, especially a memory leak on hosts with <39 physical address bits - Remove bogus EFER.NX checks on 32-bit non-PAE hosts - WAITPKG fix" * tag 'for-linus' of git://git.kernel.org/pub/scm/virt/kvm/kvm: KVM: x86/mmu: Protect marking SPs unsync when using TDP MMU with spinlock KVM: x86/mmu: Don't step down in the TDP iterator when zapping all SPTEs KVM: x86/mmu: Don't leak non-leaf SPTEs when zapping all SPTEs KVM: nVMX: Use vmx_need_pf_intercept() when deciding if L0 wants a #PF kvm: vmx: Sync all matching EPTPs when injecting nested EPT fault KVM: x86: remove dead initialization KVM: x86: Allow guest to set EFER.NX=1 on non-PAE 32-bit kernels KVM: VMX: Use current VMCS to query WAITPKG support for MSR emulation KVM: arm64: Fix race when enabling KVM_ARM_CAP_MTE KVM: arm64: Fix off-by-one in range_is_memory
2021-08-14Merge tag 'riscv-for-linus-5.14-rc6' of ↵Linus Torvalds
git://git.kernel.org/pub/scm/linux/kernel/git/riscv/linux Pull RISC-V fixes from Palmer Dabbelt: - avoid passing -mno-relax to compilers that don't support it - a comment fix * tag 'riscv-for-linus-5.14-rc6' of git://git.kernel.org/pub/scm/linux/kernel/git/riscv/linux: riscv: Fix comment regarding kernel mapping overlapping with IS_ERR_VALUE riscv: kexec: do not add '-mno-relax' flag if compiler doesn't support it
2021-08-13Merge branch 'kvm-tdpmmu-fixes' into kvm-masterPaolo Bonzini
Merge topic branch with fixes for both 5.14-rc6 and 5.15.
2021-08-13KVM: x86/mmu: Protect marking SPs unsync when using TDP MMU with spinlockSean Christopherson
Add yet another spinlock for the TDP MMU and take it when marking indirect shadow pages unsync. When using the TDP MMU and L1 is running L2(s) with nested TDP, KVM may encounter shadow pages for the TDP entries managed by L1 (controlling L2) when handling a TDP MMU page fault. The unsync logic is not thread safe, e.g. the kvm_mmu_page fields are not atomic, and misbehaves when a shadow page is marked unsync via a TDP MMU page fault, which runs with mmu_lock held for read, not write. Lack of a critical section manifests most visibly as an underflow of unsync_children in clear_unsync_child_bit() due to unsync_children being corrupted when multiple CPUs write it without a critical section and without atomic operations. But underflow is the best case scenario. The worst case scenario is that unsync_children prematurely hits '0' and leads to guest memory corruption due to KVM neglecting to properly sync shadow pages. Use an entirely new spinlock even though piggybacking tdp_mmu_pages_lock would functionally be ok. Usurping the lock could degrade performance when building upper level page tables on different vCPUs, especially since the unsync flow could hold the lock for a comparatively long time depending on the number of indirect shadow pages and the depth of the paging tree. For simplicity, take the lock for all MMUs, even though KVM could fairly easily know that mmu_lock is held for write. If mmu_lock is held for write, there cannot be contention for the inner spinlock, and marking shadow pages unsync across multiple vCPUs will be slow enough that bouncing the kvm_arch cacheline should be in the noise. Note, even though L2 could theoretically be given access to its own EPT entries, a nested MMU must hold mmu_lock for write and thus cannot race against a TDP MMU page fault. I.e. the additional spinlock only _needs_ to be taken by the TDP MMU, as opposed to being taken by any MMU for a VM that is running with the TDP MMU enabled. Holding mmu_lock for read also prevents the indirect shadow page from being freed. But as above, keep it simple and always take the lock. Alternative #1, the TDP MMU could simply pass "false" for can_unsync and effectively disable unsync behavior for nested TDP. Write protecting leaf shadow pages is unlikely to noticeably impact traditional L1 VMMs, as such VMMs typically don't modify TDP entries, but the same may not hold true for non-standard use cases and/or VMMs that are migrating physical pages (from L1's perspective). Alternative #2, the unsync logic could be made thread safe. In theory, simply converting all relevant kvm_mmu_page fields to atomics and using atomic bitops for the bitmap would suffice. However, (a) an in-depth audit would be required, (b) the code churn would be substantial, and (c) legacy shadow paging would incur additional atomic operations in performance sensitive paths for no benefit (to legacy shadow paging). Fixes: a2855afc7ee8 ("KVM: x86/mmu: Allow parallel page faults for the TDP MMU") Cc: stable@vger.kernel.org Cc: Ben Gardon <bgardon@google.com> Signed-off-by: Sean Christopherson <seanjc@google.com> Message-Id: <20210812181815.3378104-1-seanjc@google.com> Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
2021-08-13KVM: x86/mmu: Don't step down in the TDP iterator when zapping all SPTEsSean Christopherson
Set the min_level for the TDP iterator at the root level when zapping all SPTEs to optimize the iterator's try_step_down(). Zapping a non-leaf SPTE will recursively zap all its children, thus there is no need for the iterator to attempt to step down. This avoids rereading the top-level SPTEs after they are zapped by causing try_step_down() to short-circuit. In most cases, optimizing try_step_down() will be in the noise as the cost of zapping SPTEs completely dominates the overall time. The optimization is however helpful if the zap occurs with relatively few SPTEs, e.g. if KVM is zapping in response to multiple memslot updates when userspace is adding and removing read-only memslots for option ROMs. In that case, the task doing the zapping likely isn't a vCPU thread, but it still holds mmu_lock for read and thus can be a noisy neighbor of sorts. Reviewed-by: Ben Gardon <bgardon@google.com> Signed-off-by: Sean Christopherson <seanjc@google.com> Message-Id: <20210812181414.3376143-3-seanjc@google.com> Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
2021-08-13KVM: x86/mmu: Don't leak non-leaf SPTEs when zapping all SPTEsSean Christopherson
Pass "all ones" as the end GFN to signal "zap all" for the TDP MMU and really zap all SPTEs in this case. As is, zap_gfn_range() skips non-leaf SPTEs whose range exceeds the range to be zapped. If shadow_phys_bits is not aligned to the range size of top-level SPTEs, e.g. 512gb with 4-level paging, the "zap all" flows will skip top-level SPTEs whose range extends beyond shadow_phys_bits and leak their SPs when the VM is destroyed. Use the current upper bound (based on host.MAXPHYADDR) to detect that the caller wants to zap all SPTEs, e.g. instead of using the max theoretical gfn, 1 << (52 - 12). The more precise upper bound allows the TDP iterator to terminate its walk earlier when running on hosts with MAXPHYADDR < 52. Add a WARN on kmv->arch.tdp_mmu_pages when the TDP MMU is destroyed to help future debuggers should KVM decide to leak SPTEs again. The bug is most easily reproduced by running (and unloading!) KVM in a VM whose host.MAXPHYADDR < 39, as the SPTE for gfn=0 will be skipped. ============================================================================= BUG kvm_mmu_page_header (Not tainted): Objects remaining in kvm_mmu_page_header on __kmem_cache_shutdown() ----------------------------------------------------------------------------- Slab 0x000000004d8f7af1 objects=22 used=2 fp=0x00000000624d29ac flags=0x4000000000000200(slab|zone=1) CPU: 0 PID: 1582 Comm: rmmod Not tainted 5.14.0-rc2+ #420 Hardware name: QEMU Standard PC (Q35 + ICH9, 2009), BIOS 0.0.0 02/06/2015 Call Trace: dump_stack_lvl+0x45/0x59 slab_err+0x95/0xc9 __kmem_cache_shutdown.cold+0x3c/0x158 kmem_cache_destroy+0x3d/0xf0 kvm_mmu_module_exit+0xa/0x30 [kvm] kvm_arch_exit+0x5d/0x90 [kvm] kvm_exit+0x78/0x90 [kvm] vmx_exit+0x1a/0x50 [kvm_intel] __x64_sys_delete_module+0x13f/0x220 do_syscall_64+0x3b/0xc0 entry_SYSCALL_64_after_hwframe+0x44/0xae Fixes: faaf05b00aec ("kvm: x86/mmu: Support zapping SPTEs in the TDP MMU") Cc: stable@vger.kernel.org Cc: Ben Gardon <bgardon@google.com> Signed-off-by: Sean Christopherson <seanjc@google.com> Message-Id: <20210812181414.3376143-2-seanjc@google.com> Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
2021-08-13Merge tag 'kvmarm-fixes-5.14-2' of ↵Paolo Bonzini
git://git.kernel.org/pub/scm/linux/kernel/git/kvmarm/kvmarm into HEAD KVM/arm64 fixes for 5.14, take #2 - Plug race between enabling MTE and creating vcpus - Fix off-by-one bug when checking whether an address range is RAM
2021-08-13KVM: nVMX: Use vmx_need_pf_intercept() when deciding if L0 wants a #PFSean Christopherson
Use vmx_need_pf_intercept() when determining if L0 wants to handle a #PF in L2 or if the VM-Exit should be forwarded to L1. The current logic fails to account for the case where #PF is intercepted to handle guest.MAXPHYADDR < host.MAXPHYADDR and ends up reflecting all #PFs into L1. At best, L1 will complain and inject the #PF back into L2. At worst, L1 will eat the unexpected fault and cause L2 to hang on infinite page faults. Note, while the bug was technically introduced by the commit that added support for the MAXPHYADDR madness, the shame is all on commit a0c134347baf ("KVM: VMX: introduce vmx_need_pf_intercept"). Fixes: 1dbf5d68af6f ("KVM: VMX: Add guest physical address check in EPT violation and misconfig") Cc: stable@vger.kernel.org Cc: Peter Shier <pshier@google.com> Cc: Oliver Upton <oupton@google.com> Cc: Jim Mattson <jmattson@google.com> Signed-off-by: Sean Christopherson <seanjc@google.com> Message-Id: <20210812045615.3167686-1-seanjc@google.com> Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
2021-08-13kvm: vmx: Sync all matching EPTPs when injecting nested EPT faultJunaid Shahid
When a nested EPT violation/misconfig is injected into the guest, the shadow EPT PTEs associated with that address need to be synced. This is done by kvm_inject_emulated_page_fault() before it calls nested_ept_inject_page_fault(). However, that will only sync the shadow EPT PTE associated with the current L1 EPTP. Since the ASID is based on EP4TA rather than the full EPTP, so syncing the current EPTP is not enough. The SPTEs associated with any other L1 EPTPs in the prev_roots cache with the same EP4TA also need to be synced. Signed-off-by: Junaid Shahid <junaids@google.com> Message-Id: <20210806222229.1645356-1-junaids@google.com> Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
2021-08-13Merge branch 'kvm-vmx-secctl' into kvm-masterPaolo Bonzini
Merge common topic branch for 5.14-rc6 and 5.15 merge window.
2021-08-13KVM: x86: remove dead initializationPaolo Bonzini
hv_vcpu is initialized again a dozen lines below, and at this point vcpu->arch.hyperv is not valid. Remove the initializer. Reported-by: kernel test robot <lkp@intel.com> Reviewed-by: Sean Christopherson <seanjc@google.com> Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
2021-08-13KVM: x86: Allow guest to set EFER.NX=1 on non-PAE 32-bit kernelsSean Christopherson
Remove an ancient restriction that disallowed exposing EFER.NX to the guest if EFER.NX=0 on the host, even if NX is fully supported by the CPU. The motivation of the check, added by commit 2cc51560aed0 ("KVM: VMX: Avoid saving and restoring msr_efer on lightweight vmexit"), was to rule out the case of host.EFER.NX=0 and guest.EFER.NX=1 so that KVM could run the guest with the host's EFER.NX and thus avoid context switching EFER if the only divergence was the NX bit. Fast forward to today, and KVM has long since stopped running the guest with the host's EFER.NX. Not only does KVM context switch EFER if host.EFER.NX=1 && guest.EFER.NX=0, KVM also forces host.EFER.NX=0 && guest.EFER.NX=1 when using shadow paging (to emulate SMEP). Furthermore, the entire motivation for the restriction was made obsolete over a decade ago when Intel added dedicated host and guest EFER fields in the VMCS (Nehalem timeframe), which reduced the overhead of context switching EFER from 400+ cycles (2 * WRMSR + 1 * RDMSR) to a mere ~2 cycles. In practice, the removed restriction only affects non-PAE 32-bit kernels, as EFER.NX is set during boot if NX is supported and the kernel will use PAE paging (32-bit or 64-bit), regardless of whether or not the kernel will actually use NX itself (mark PTEs non-executable). Alternatively and/or complementarily, startup_32_smp() in head_32.S could be modified to set EFER.NX=1 regardless of paging mode, thus eliminating the scenario where NX is supported but not enabled. However, that runs the risk of breaking non-KVM non-PAE kernels (though the risk is very, very low as there are no known EFER.NX errata), and also eliminates an easy-to-use mechanism for stressing KVM's handling of guest vs. host EFER across nested virtualization transitions. Suggested-by: Paolo Bonzini <pbonzini@redhat.com> Signed-off-by: Sean Christopherson <seanjc@google.com> Message-Id: <20210805183804.1221554-1-seanjc@google.com> Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>