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2021-06-21swiotlb: manipulate orig_addr when tlb_addr has offsetBumyong Lee
in case of driver wants to sync part of ranges with offset, swiotlb_tbl_sync_single() copies from orig_addr base to tlb_addr with offset and ends up with data mismatch. It was removed from "swiotlb: don't modify orig_addr in swiotlb_tbl_sync_single", but said logic has to be added back in. From Linus's email: "That commit which the removed the offset calculation entirely, because the old (unsigned long)tlb_addr & (IO_TLB_SIZE - 1) was wrong, but instead of removing it, I think it should have just fixed it to be (tlb_addr - mem->start) & (IO_TLB_SIZE - 1); instead. That way the slot offset always matches the slot index calculation." (Unfortunatly that broke NVMe). The use-case that drivers are hitting is as follow: 1. Get dma_addr_t from dma_map_single() dma_addr_t tlb_addr = dma_map_single(dev, vaddr, vsize, DMA_TO_DEVICE); |<---------------vsize------------->| +-----------------------------------+ | | original buffer +-----------------------------------+ vaddr swiotlb_align_offset |<----->|<---------------vsize------------->| +-------+-----------------------------------+ | | | swiotlb buffer +-------+-----------------------------------+ tlb_addr 2. Do something 3. Sync dma_addr_t through dma_sync_single_for_device(..) dma_sync_single_for_device(dev, tlb_addr + offset, size, DMA_TO_DEVICE); Error case. Copy data to original buffer but it is from base addr (instead of base addr + offset) in original buffer: swiotlb_align_offset |<----->|<- offset ->|<- size ->| +-------+-----------------------------------+ | | |##########| | swiotlb buffer +-------+-----------------------------------+ tlb_addr |<- size ->| +-----------------------------------+ |##########| | original buffer +-----------------------------------+ vaddr The fix is to copy the data to the original buffer and take into account the offset, like so: swiotlb_align_offset |<----->|<- offset ->|<- size ->| +-------+-----------------------------------+ | | |##########| | swiotlb buffer +-------+-----------------------------------+ tlb_addr |<- offset ->|<- size ->| +-----------------------------------+ | |##########| | original buffer +-----------------------------------+ vaddr [One fix which was Linus's that made more sense to as it created a symmetry would break NVMe. The reason for that is the: unsigned int offset = (tlb_addr - mem->start) & (IO_TLB_SIZE - 1); would come up with the proper offset, but it would lose the alignment (which this patch contains).] Fixes: 16fc3cef33a0 ("swiotlb: don't modify orig_addr in swiotlb_tbl_sync_single") Signed-off-by: Bumyong Lee <bumyong.lee@samsung.com> Signed-off-by: Chanho Park <chanho61.park@samsung.com> Reviewed-by: Christoph Hellwig <hch@lst.de> Reported-by: Dominique MARTINET <dominique.martinet@atmark-techno.com> Reported-by: Horia Geantă <horia.geanta@nxp.com> Tested-by: Horia Geantă <horia.geanta@nxp.com> CC: stable@vger.kernel.org Signed-off-by: Konrad Rzeszutek Wilk <konrad.wilk@oracle.com>
2021-04-29swiotlb: don't override user specified size in swiotlb_adjust_sizeChristoph Hellwig
If the user already specified a swiotlb size on the command line, swiotlb_adjust_size should not overwrite it. Fixes: 2cbc2776efe4 ("swiotlb: remove swiotlb_nr_tbl") Reported-by: Tom Lendacky <thomas.lendacky@amd.com> Tested-by: Tom Lendacky <thomas.lendacky@amd.com> Signed-off-by: Christoph Hellwig <hch@lst.de> Signed-off-by: Konrad Rzeszutek Wilk <konrad.wilk@oracle.com>
2021-04-27swiotlb: Fix the type of indexClaire Chang
Fix the type of index from unsigned int to int since find_slots() might return -1. Fixes: 26a7e094783d ("swiotlb: refactor swiotlb_tbl_map_single") Reviewed-by: Christoph Hellwig <hch@lst.de> Signed-off-by: Claire Chang <tientzu@chromium.org> Signed-off-by: Konrad Rzeszutek Wilk <konrad@kernel.org>
2021-04-01swiotlb: Make SWIOTLB_NO_FORCE perform no allocationFlorian Fainelli
When SWIOTLB_NO_FORCE is used, there should really be no allocations of default_nslabs to occur since we are not going to use those slabs. If a platform was somehow setting swiotlb_no_force and a later call to swiotlb_init() was to be made we would still be proceeding with allocating the default SWIOTLB size (64MB), whereas if swiotlb=noforce was set on the kernel command line we would have only allocated 2KB. This would be inconsistent and the point of initializing default_nslabs to 1, was intended to allocate the minimum amount of memory possible, so simply remove that minimal allocation period. Signed-off-by: Florian Fainelli <f.fainelli@gmail.com> Reviewed-by: Christoph Hellwig <hch@lst.de> Signed-off-by: Konrad Rzeszutek Wilk <konrad.wilk@oracle.com>
2021-03-19ARM: Qualify enabling of swiotlb_init()Florian Fainelli
We do not need a SWIOTLB unless we have DRAM that is addressable beyond the arm_dma_limit. Compare max_pfn with arm_dma_pfn_limit to determine whether we do need a SWIOTLB to be initialized. Fixes: ad3c7b18c5b3 ("arm: use swiotlb for bounce buffering on LPAE configs") Signed-off-by: Florian Fainelli <f.fainelli@gmail.com> Signed-off-by: Konrad Rzeszutek Wilk <konrad.wilk@oracle.com>
2021-03-19swiotlb: remove swiotlb_nr_tblChristoph Hellwig
All callers just use it to check if swiotlb is active at all, for which they can just use is_swiotlb_active. In the longer run drivers need to stop using is_swiotlb_active as well, but let's do the simple step first. Signed-off-by: Christoph Hellwig <hch@lst.de> Signed-off-by: Konrad Rzeszutek Wilk <konrad.wilk@oracle.com>
2021-03-19swiotlb: dynamically allocate io_tlb_default_memChristoph Hellwig
Instead of allocating ->list and ->orig_addr separately just do one dynamic allocation for the actual io_tlb_mem structure. This simplifies a lot of the initialization code, and also allows to just check io_tlb_default_mem to see if swiotlb is in use. Signed-off-by: Christoph Hellwig <hch@lst.de> Signed-off-by: Konrad Rzeszutek Wilk <konrad.wilk@oracle.com>
2021-03-19swiotlb: move global variables into a new io_tlb_mem structureClaire Chang
Added a new struct, io_tlb_mem, as the IO TLB memory pool descriptor and moved relevant global variables into that struct. This will be useful later to allow for restricted DMA pool. Signed-off-by: Claire Chang <tientzu@chromium.org> [hch: rebased] Signed-off-by: Christoph Hellwig <hch@lst.de> Signed-off-by: Konrad Rzeszutek Wilk <konrad.wilk@oracle.com>
2021-03-17xen-swiotlb: remove the unused size argument from xen_swiotlb_fixupChristoph Hellwig
Signed-off-by: Christoph Hellwig <hch@lst.de> Signed-off-by: Konrad Rzeszutek Wilk <konrad.wilk@oracle.com>
2021-03-17xen-swiotlb: split xen_swiotlb_initChristoph Hellwig
Split xen_swiotlb_init into a normal an an early case. That makes both much simpler and more readable, and also allows marking the early code as __init and x86-only. Signed-off-by: Christoph Hellwig <hch@lst.de> Signed-off-by: Konrad Rzeszutek Wilk <konrad.wilk@oracle.com>
2021-03-17swiotlb: lift the double initialization protection from xen-swiotlbChristoph Hellwig
Lift the double initialization protection from xen-swiotlb to the core code to avoid exposing too many swiotlb internals. Also upgrade the check to a warning as it should not happen. Signed-off-by: Christoph Hellwig <hch@lst.de> Signed-off-by: Konrad Rzeszutek Wilk <konrad.wilk@oracle.com>
2021-03-17xen-swiotlb: remove xen_io_tlb_start and xen_io_tlb_nslabsChristoph Hellwig
The xen_io_tlb_start and xen_io_tlb_nslabs variables are now only used in xen_swiotlb_init, so replace them with local variables. Signed-off-by: Christoph Hellwig <hch@lst.de> Signed-off-by: Konrad Rzeszutek Wilk <konrad.wilk@oracle.com>
2021-03-17xen-swiotlb: remove xen_set_nslabsChristoph Hellwig
The xen_set_nslabs function is a little weird, as it has just one caller, that caller passes a global variable as the argument, which is then overriden in the function and a derivative of it returned. Just add a cpp symbol for the default size using a readable constant and open code the remaining three lines in the caller. Signed-off-by: Christoph Hellwig <hch@lst.de> Signed-off-by: Konrad Rzeszutek Wilk <konrad.wilk@oracle.com>
2021-03-17xen-swiotlb: use io_tlb_end in xen_swiotlb_dma_supportedChristoph Hellwig
Use the existing variable that holds the physical address for xen_io_tlb_end to simplify xen_swiotlb_dma_supported a bit, and remove the otherwise unused xen_io_tlb_end variable and the xen_virt_to_bus helper. Signed-off-by: Christoph Hellwig <hch@lst.de> Signed-off-by: Konrad Rzeszutek Wilk <konrad.wilk@oracle.com>
2021-03-17xen-swiotlb: use is_swiotlb_buffer in is_xen_swiotlb_bufferChristoph Hellwig
Use the is_swiotlb_buffer to check if a physical address is a swiotlb buffer. This works because xen-swiotlb does use the same buffer as the main swiotlb code, and xen_io_tlb_{start,end} are just the addresses for it that went through phys_to_virt. Signed-off-by: Christoph Hellwig <hch@lst.de> Signed-off-by: Konrad Rzeszutek Wilk <konrad.wilk@oracle.com>
2021-03-17swiotlb: split swiotlb_tbl_sync_singleChristoph Hellwig
Split swiotlb_tbl_sync_single into two separate funtions for the to device and to cpu synchronization. Signed-off-by: Christoph Hellwig <hch@lst.de> Signed-off-by: Konrad Rzeszutek Wilk <konrad.wilk@oracle.com>
2021-03-17swiotlb: move orig addr and size validation into swiotlb_bounceChristoph Hellwig
Move the code to find and validate the original buffer address and size from the callers into swiotlb_bounce. This means a tiny bit of extra work in the swiotlb_map path, but avoids code duplication and a leads to a better code structure. Signed-off-by: Christoph Hellwig <hch@lst.de> Signed-off-by: Konrad Rzeszutek Wilk <konrad.wilk@oracle.com>
2021-03-17swiotlb: remove the alloc_size parameter to swiotlb_tbl_unmap_singleChristoph Hellwig
Now that swiotlb remembers the allocation size there is no need to pass it back to swiotlb_tbl_unmap_single. Signed-off-by: Christoph Hellwig <hch@lst.de> Signed-off-by: Konrad Rzeszutek Wilk <konrad.wilk@oracle.com>
2021-03-17powerpc/svm: stop using io_tlb_startChristoph Hellwig
Use the local variable that is passed to swiotlb_init_with_tbl for freeing the memory in the failure case to isolate the code a little better from swiotlb internals. Signed-off-by: Christoph Hellwig <hch@lst.de> Signed-off-by: Konrad Rzeszutek Wilk <konrad.wilk@oracle.com>
2021-03-14Linux 5.12-rc3Linus Torvalds
2021-03-14prctl: fix PR_SET_MM_AUXV kernel stack leakAlexey Dobriyan
Doing a prctl(PR_SET_MM, PR_SET_MM_AUXV, addr, 1); will copy 1 byte from userspace to (quite big) on-stack array and then stash everything to mm->saved_auxv. AT_NULL terminator will be inserted at the very end. /proc/*/auxv handler will find that AT_NULL terminator and copy original stack contents to userspace. This devious scheme requires CAP_SYS_RESOURCE. Signed-off-by: Alexey Dobriyan <adobriyan@gmail.com> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2021-03-14Merge tag 'irq-urgent-2021-03-14' of ↵Linus Torvalds
git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip Pull irq fixes from Thomas Gleixner: "A set of irqchip updates: - Make the GENERIC_IRQ_MULTI_HANDLER configuration correct - Add a missing DT compatible string for the Ingenic driver - Remove the pointless debugfs_file pointer from struct irqdomain" * tag 'irq-urgent-2021-03-14' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip: irqchip/ingenic: Add support for the JZ4760 dt-bindings/irq: Add compatible string for the JZ4760B irqchip: Do not blindly select CONFIG_GENERIC_IRQ_MULTI_HANDLER ARM: ep93xx: Select GENERIC_IRQ_MULTI_HANDLER directly irqdomain: Remove debugfs_file from struct irq_domain
2021-03-14Merge tag 'timers-urgent-2021-03-14' of ↵Linus Torvalds
git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip Pull timer fix from Thomas Gleixner: "A single fix in for hrtimers to prevent an interrupt storm caused by the lack of reevaluation of the timers which expire in softirq context under certain circumstances, e.g. when the clock was set" * tag 'timers-urgent-2021-03-14' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip: hrtimer: Update softirq_expires_next correctly after __hrtimer_get_next_event()
2021-03-14Merge tag 'sched-urgent-2021-03-14' of ↵Linus Torvalds
git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip Pull scheduler fixes from Thomas Gleixner: "A set of scheduler updates: - Prevent a NULL pointer dereference in the migration_stop_cpu() mechanims - Prevent self concurrency of affine_move_task() - Small fixes and cleanups related to task migration/affinity setting - Ensure that sync_runqueues_membarrier_state() is invoked on the current CPU when it is in the cpu mask" * tag 'sched-urgent-2021-03-14' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip: sched/membarrier: fix missing local execution of ipi_sync_rq_state() sched: Simplify set_affinity_pending refcounts sched: Fix affine_move_task() self-concurrency sched: Optimize migration_cpu_stop() sched: Collate affine_move_task() stoppers sched: Simplify migration_cpu_stop() sched: Fix migration_cpu_stop() requeueing
2021-03-14Merge tag 'objtool-urgent-2021-03-14' of ↵Linus Torvalds
git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip Pull objtool fix from Thomas Gleixner: "A single objtool fix to handle the PUSHF/POPF validation correctly for the paravirt changes which modified arch_local_irq_restore not to use popf" * tag 'objtool-urgent-2021-03-14' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip: objtool,x86: Fix uaccess PUSHF/POPF validation
2021-03-14Merge tag 'locking-urgent-2021-03-14' of ↵Linus Torvalds
git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip Pull locking fixes from Thomas Gleixner: "A couple of locking fixes: - A fix for the static_call mechanism so it handles unaligned addresses correctly. - Make u64_stats_init() a macro so every instance gets a seperate lockdep key. - Make seqcount_latch_init() a macro as well to preserve the static variable which is used for the lockdep key" * tag 'locking-urgent-2021-03-14' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip: seqlock,lockdep: Fix seqcount_latch_init() u64_stats,lockdep: Fix u64_stats_init() vs lockdep static_call: Fix the module key fixup
2021-03-14Merge tag 'perf_urgent_for_v5.12-rc3' of ↵Linus Torvalds
git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip Pull perf fixes from Borislav Petkov: - Make sure PMU internal buffers are flushed for per-CPU events too and properly handle PID/TID for large PEBS. - Handle the case properly when there's no PMU and therefore return an empty list of perf MSRs for VMX to switch instead of reading random garbage from the stack. * tag 'perf_urgent_for_v5.12-rc3' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip: x86/perf: Use RET0 as default for guest_get_msrs to handle "no PMU" case perf/x86/intel: Set PERF_ATTACH_SCHED_CB for large PEBS and LBR perf/core: Flush PMU internal buffers for per-CPU events
2021-03-14Merge tag 'efi-urgent-for-v5.12-rc2' of ↵Linus Torvalds
git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip Pull EFI fix from Ard Biesheuvel via Borislav Petkov: "Fix an oversight in the handling of EFI_RT_PROPERTIES_TABLE, which was added v5.10, but failed to take the SetVirtualAddressMap() RT service into account" * tag 'efi-urgent-for-v5.12-rc2' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip: efi: stub: omit SetVirtualAddressMap() if marked unsupported in RT_PROP table
2021-03-14Merge tag 'x86_urgent_for_v5.12_rc3' of ↵Linus Torvalds
git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip Pull x86 fixes from Borislav Petkov: - A couple of SEV-ES fixes and robustifications: verify usermode stack pointer in NMI is not coming from the syscall gap, correctly track IRQ states in the #VC handler and access user insn bytes atomically in same handler as latter cannot sleep. - Balance 32-bit fast syscall exit path to do the proper work on exit and thus not confuse audit and ptrace frameworks. - Two fixes for the ORC unwinder going "off the rails" into KASAN redzones and when ORC data is missing. * tag 'x86_urgent_for_v5.12_rc3' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip: x86/sev-es: Use __copy_from_user_inatomic() x86/sev-es: Correctly track IRQ states in runtime #VC handler x86/sev-es: Check regs->sp is trusted before adjusting #VC IST stack x86/sev-es: Introduce ip_within_syscall_gap() helper x86/entry: Fix entry/exit mismatch on failed fast 32-bit syscalls x86/unwind/orc: Silence warnings caused by missing ORC data x86/unwind/orc: Disable KASAN checking in the ORC unwinder, part 2
2021-03-14Merge tag 'powerpc-5.12-3' of ↵Linus Torvalds
git://git.kernel.org/pub/scm/linux/kernel/git/powerpc/linux Pull powerpc fixes from Michael Ellerman: "Some more powerpc fixes for 5.12: - Fix wrong instruction encoding for lis in ppc_function_entry(), which could potentially lead to missed kprobes. - Fix SET_FULL_REGS on 32-bit and 64e, which prevented ptrace of non-volatile GPRs immediately after exec. - Clean up a missed SRR specifier in the recent interrupt rework. - Don't treat unrecoverable_exception() as an interrupt handler, it's called from other handlers so shouldn't do the interrupt entry/exit accounting itself. - Fix build errors caused by missing declarations for [en/dis]able_kernel_vsx(). Thanks to Christophe Leroy, Daniel Axtens, Geert Uytterhoeven, Jiri Olsa, Naveen N. Rao, and Nicholas Piggin" * tag 'powerpc-5.12-3' of git://git.kernel.org/pub/scm/linux/kernel/git/powerpc/linux: powerpc/traps: unrecoverable_exception() is not an interrupt handler powerpc: Fix missing declaration of [en/dis]able_kernel_vsx() powerpc/64s/exception: Clean up a missed SRR specifier powerpc: Fix inverted SET_FULL_REGS bitop powerpc/64s: Use symbolic macros for function entry encoding powerpc/64s: Fix instruction encoding for lis in ppc_function_entry()
2021-03-14Merge tag 'for-linus' of git://git.kernel.org/pub/scm/virt/kvm/kvmLinus Torvalds
Pull KVM fixes from Paolo Bonzini: "More fixes for ARM and x86" * tag 'for-linus' of git://git.kernel.org/pub/scm/virt/kvm/kvm: KVM: LAPIC: Advancing the timer expiration on guest initiated write KVM: x86/mmu: Skip !MMU-present SPTEs when removing SP in exclusive mode KVM: kvmclock: Fix vCPUs > 64 can't be online/hotpluged kvm: x86: annotate RCU pointers KVM: arm64: Fix exclusive limit for IPA size KVM: arm64: Reject VM creation when the default IPA size is unsupported KVM: arm64: Ensure I-cache isolation between vcpus of a same VM KVM: arm64: Don't use cbz/adr with external symbols KVM: arm64: Fix range alignment when walking page tables KVM: arm64: Workaround firmware wrongly advertising GICv2-on-v3 compatibility KVM: arm64: Rename __vgic_v3_get_ich_vtr_el2() to __vgic_v3_get_gic_config() KVM: arm64: Don't access PMSELR_EL0/PMUSERENR_EL0 when no PMU is available KVM: arm64: Turn kvm_arm_support_pmu_v3() into a static key KVM: arm64: Fix nVHE hyp panic host context restore KVM: arm64: Avoid corrupting vCPU context register in guest exit KVM: arm64: nvhe: Save the SPE context early kvm: x86: use NULL instead of using plain integer as pointer KVM: SVM: Connect 'npt' module param to KVM's internal 'npt_enabled' KVM: x86: Ensure deadline timer has truly expired before posting its IRQ
2021-03-14Merge branch 'akpm' (patches from Andrew)Linus Torvalds
Merge misc fixes from Andrew Morton: "28 patches. Subsystems affected by this series: mm (memblock, pagealloc, hugetlb, highmem, kfence, oom-kill, madvise, kasan, userfaultfd, memcg, and zram), core-kernel, kconfig, fork, binfmt, MAINTAINERS, kbuild, and ia64" * emailed patches from Andrew Morton <akpm@linux-foundation.org>: (28 commits) zram: fix broken page writeback zram: fix return value on writeback_store mm/memcg: set memcg when splitting page mm/memcg: rename mem_cgroup_split_huge_fixup to split_page_memcg and add nr_pages argument ia64: fix ptrace(PTRACE_SYSCALL_INFO_EXIT) sign ia64: fix ia64_syscall_get_set_arguments() for break-based syscalls mm/userfaultfd: fix memory corruption due to writeprotect kasan: fix KASAN_STACK dependency for HW_TAGS kasan, mm: fix crash with HW_TAGS and DEBUG_PAGEALLOC mm/madvise: replace ptrace attach requirement for process_madvise include/linux/sched/mm.h: use rcu_dereference in in_vfork() kfence: fix reports if constant function prefixes exist kfence, slab: fix cache_alloc_debugcheck_after() for bulk allocations kfence: fix printk format for ptrdiff_t linux/compiler-clang.h: define HAVE_BUILTIN_BSWAP* MAINTAINERS: exclude uapi directories in API/ABI section binfmt_misc: fix possible deadlock in bm_register_write mm/highmem.c: fix zero_user_segments() with start > end hugetlb: do early cow when page pinned on src mm mm: use is_cow_mapping() across tree where proper ...
2021-03-14Merge tag 'irqchip-fixes-5.12-1' of ↵Thomas Gleixner
git://git.kernel.org/pub/scm/linux/kernel/git/maz/arm-platforms into irq/urgent Pull irqchip fixes from Marc Zyngier: - More compatible strings for the Ingenic irqchip (introducing the JZ4760B SoC) - Select GENERIC_IRQ_MULTI_HANDLER on the ARM ep93xx platform - Drop all GENERIC_IRQ_MULTI_HANDLER selections from the irqchip Kconfig, now relying on the architecture to get it right - Drop the debugfs_file field from struct irq_domain, now that debugfs can track things on its own
2021-03-13Merge tag 'char-misc-5.12-rc3' of ↵Linus Torvalds
git://git.kernel.org/pub/scm/linux/kernel/git/gregkh/char-misc Pull char/misc driver fixes from Greg KH: "Here are some small misc/char driver fixes to resolve some reported problems: - habanalabs driver fixes - Acrn build fixes (reported many times) - pvpanic module table export fix All of these have been in linux-next for a while with no reported issues" * tag 'char-misc-5.12-rc3' of git://git.kernel.org/pub/scm/linux/kernel/git/gregkh/char-misc: misc/pvpanic: Export module FDT device table misc: fastrpc: restrict user apps from sending kernel RPC messages virt: acrn: Correct type casting of argument of copy_from_user() virt: acrn: Use EPOLLIN instead of POLLIN virt: acrn: Use vfs_poll() instead of f_op->poll() virt: acrn: Make remove_cpu sysfs invisible with !CONFIG_HOTPLUG_CPU cpu/hotplug: Fix build error of using {add,remove}_cpu() with !CONFIG_SMP habanalabs: fix debugfs address translation habanalabs: Disable file operations after device is removed habanalabs: Call put_pid() when releasing control device drivers: habanalabs: remove unused dentry pointer for debugfs files habanalabs: mark hl_eq_inc_ptr() as static
2021-03-13Merge tag 'staging-5.12-rc3' of ↵Linus Torvalds
git://git.kernel.org/pub/scm/linux/kernel/git/gregkh/staging Pull staging driver fixes from Greg KH: "Here are some small staging driver fixes for reported problems. They include: - wfx header file cleanup patch reverted as it could cause problems - comedi driver endian fixes - buffer overflow problems for staging wifi drivers - build dependency issue for rtl8192e driver All have been in linux-next for a while with no reported problems" * tag 'staging-5.12-rc3' of git://git.kernel.org/pub/scm/linux/kernel/git/gregkh/staging: (23 commits) Revert "staging: wfx: remove unused included header files" staging: rtl8188eu: prevent ->ssid overflow in rtw_wx_set_scan() staging: rtl8188eu: fix potential memory corruption in rtw_check_beacon_data() staging: rtl8192u: fix ->ssid overflow in r8192_wx_set_scan() staging: comedi: pcl726: Use 16-bit 0 for interrupt data staging: comedi: ni_65xx: Use 16-bit 0 for interrupt data staging: comedi: ni_6527: Use 16-bit 0 for interrupt data staging: comedi: comedi_parport: Use 16-bit 0 for interrupt data staging: comedi: amplc_pc236_common: Use 16-bit 0 for interrupt data staging: comedi: pcl818: Fix endian problem for AI command data staging: comedi: pcl711: Fix endian problem for AI command data staging: comedi: me4000: Fix endian problem for AI command data staging: comedi: dmm32at: Fix endian problem for AI command data staging: comedi: das800: Fix endian problem for AI command data staging: comedi: das6402: Fix endian problem for AI command data staging: comedi: adv_pci1710: Fix endian problem for AI command data staging: comedi: addi_apci_1500: Fix endian problem for command sample staging: comedi: addi_apci_1032: Fix endian problem for COS sample staging: ks7010: prevent buffer overflow in ks_wlan_set_scan() staging: rtl8712: Fix possible buffer overflow in r8712_sitesurvey_cmd ...
2021-03-13Merge tag 'tty-5.12-rc3' of ↵Linus Torvalds
git://git.kernel.org/pub/scm/linux/kernel/git/gregkh/tty Pull tty/serial fixes from Greg KH: "Here are some small tty and serial driver fixes to resolve some reported problems: - led tty trigger fixes based on review and were acked by the led maintainer - revert a max310x serial driver patch as it was causing problems - revert a pty change as it was also causing problems All of these have been in linux-next for a while with no reported problems" * tag 'tty-5.12-rc3' of git://git.kernel.org/pub/scm/linux/kernel/git/gregkh/tty: Revert "drivers:tty:pty: Fix a race causing data loss on close" Revert "serial: max310x: rework RX interrupt handling" leds: trigger/tty: Use led_set_brightness_sync() from workqueue leds: trigger: Fix error path to not unlock the unlocked mutex
2021-03-13Merge tag 'usb-5.12-rc3' of ↵Linus Torvalds
git://git.kernel.org/pub/scm/linux/kernel/git/gregkh/usb Pull USB fixes from Greg KH: "Here are a small number of USB fixes for 5.12-rc3 to resolve a bunch of reported issues: - usbip fixups for issues found by syzbot - xhci driver fixes and quirk additions - gadget driver fixes - dwc3 QCOM driver fix - usb-serial new ids and fixes - usblp fix for a long-time issue - cdc-acm quirk addition - other tiny fixes for reported problems All of these have been in linux-next for a while with no reported issues" * tag 'usb-5.12-rc3' of git://git.kernel.org/pub/scm/linux/kernel/git/gregkh/usb: (25 commits) xhci: Fix repeated xhci wake after suspend due to uncleared internal wake state usb: xhci: Fix ASMedia ASM1042A and ASM3242 DMA addressing xhci: Improve detection of device initiated wake signal. usb: xhci: do not perform Soft Retry for some xHCI hosts usbip: fix vudc usbip_sockfd_store races leading to gpf usbip: fix vhci_hcd attach_store() races leading to gpf usbip: fix stub_dev usbip_sockfd_store() races leading to gpf usbip: fix vudc to check for stream socket usbip: fix vhci_hcd to check for stream socket usbip: fix stub_dev to check for stream socket usb: dwc3: qcom: Add missing DWC3 OF node refcount decrement USB: usblp: fix a hang in poll() if disconnected USB: gadget: udc: s3c2410_udc: fix return value check in s3c2410_udc_probe() usb: renesas_usbhs: Clear PIPECFG for re-enabling pipe with other EPNUM usb: dwc3: qcom: Honor wakeup enabled/disabled state usb: gadget: f_uac1: stop playback on function disable usb: gadget: f_uac2: always increase endpoint max_packet_size by one audio slot USB: gadget: u_ether: Fix a configfs return code usb: dwc3: qcom: add ACPI device id for sc8180x Goodix Fingerprint device is not a modem ...
2021-03-13Merge tag 'erofs-for-5.12-rc3' of ↵Linus Torvalds
git://git.kernel.org/pub/scm/linux/kernel/git/xiang/erofs Pull erofs fix from Gao Xiang: "Fix an urgent regression introduced by commit baa2c7c97153 ("block: set .bi_max_vecs as actual allocated vector number"), which could cause unexpected hung since linux 5.12-rc1. Resolve it by avoiding using bio->bi_max_vecs completely" * tag 'erofs-for-5.12-rc3' of git://git.kernel.org/pub/scm/linux/kernel/git/xiang/erofs: erofs: fix bio->bi_max_vecs behavior change
2021-03-13Merge tag 'kbuild-fixes-v5.12-2' of ↵Linus Torvalds
git://git.kernel.org/pub/scm/linux/kernel/git/masahiroy/linux-kbuild Pull Kbuild fixes from Masahiro Yamada: - avoid 'make image_name' invoking syncconfig - fix a couple of bugs in scripts/dummy-tools - fix LLD_VENDOR and locale issues in scripts/ld-version.sh - rebuild GCC plugins when the compiler is upgraded - allow LTO to be enabled with KASAN_HW_TAGS - allow LTO to be enabled without LLVM=1 * tag 'kbuild-fixes-v5.12-2' of git://git.kernel.org/pub/scm/linux/kernel/git/masahiroy/linux-kbuild: kbuild: fix ld-version.sh to not be affected by locale kbuild: remove meaningless parameter to $(call if_changed_rule,dtc) kbuild: remove LLVM=1 test from HAS_LTO_CLANG kbuild: remove unneeded -O option to dtc kbuild: dummy-tools: adjust to scripts/cc-version.sh kbuild: Allow LTO to be selected with KASAN_HW_TAGS kbuild: dummy-tools: support MPROFILE_KERNEL checks for ppc kbuild: rebuild GCC plugins when the compiler is upgraded kbuild: Fix ld-version.sh script if LLD was built with LLD_VENDOR kbuild: dummy-tools: fix inverted tests for gcc kbuild: add image_name to no-sync-config-targets
2021-03-13zram: fix broken page writebackMinchan Kim
commit 0d8359620d9b ("zram: support page writeback") introduced two problems. It overwrites writeback_store's return value as kstrtol's return value, which makes return value zero so user could see zero as return value of write syscall even though it wrote data successfully. It also breaks index value in the loop in that it doesn't increase the index any longer. It means it can write only first starting block index so user couldn't write all idle pages in the zram so lose memory saving chance. This patch fixes those issues. Link: https://lkml.kernel.org/r/20210312173949.2197662-2-minchan@kernel.org Fixes: 0d8359620d9b("zram: support page writeback") Signed-off-by: Minchan Kim <minchan@kernel.org> Reported-by: Amos Bianchi <amosbianchi@google.com> Cc: Sergey Senozhatsky <sergey.senozhatsky@gmail.com> Cc: John Dias <joaodias@google.com> Cc: <stable@vger.kernel.org> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2021-03-13zram: fix return value on writeback_storeMinchan Kim
writeback_store's return value is overwritten by submit_bio_wait's return value. Thus, writeback_store will return zero since there was no IO error. In the end, write syscall from userspace will see the zero as return value, which could make the process stall to keep trying the write until it will succeed. Link: https://lkml.kernel.org/r/20210312173949.2197662-1-minchan@kernel.org Fixes: 3b82a051c101("drivers/block/zram/zram_drv.c: fix error return codes not being returned in writeback_store") Signed-off-by: Minchan Kim <minchan@kernel.org> Cc: Sergey Senozhatsky <sergey.senozhatsky@gmail.com> Cc: Colin Ian King <colin.king@canonical.com> Cc: John Dias <joaodias@google.com> Cc: <stable@vger.kernel.org> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2021-03-13mm/memcg: set memcg when splitting pageZhou Guanghui
As described in the split_page() comment, for the non-compound high order page, the sub-pages must be freed individually. If the memcg of the first page is valid, the tail pages cannot be uncharged when be freed. For example, when alloc_pages_exact is used to allocate 1MB continuous physical memory, 2MB is charged(kmemcg is enabled and __GFP_ACCOUNT is set). When make_alloc_exact free the unused 1MB and free_pages_exact free the applied 1MB, actually, only 4KB(one page) is uncharged. Therefore, the memcg of the tail page needs to be set when splitting a page. Michel: There are at least two explicit users of __GFP_ACCOUNT with alloc_exact_pages added recently. See 7efe8ef274024 ("KVM: arm64: Allocate stage-2 pgd pages with GFP_KERNEL_ACCOUNT") and c419621873713 ("KVM: s390: Add memcg accounting to KVM allocations"), so this is not just a theoretical issue. Link: https://lkml.kernel.org/r/20210304074053.65527-3-zhouguanghui1@huawei.com Signed-off-by: Zhou Guanghui <zhouguanghui1@huawei.com> Acked-by: Johannes Weiner <hannes@cmpxchg.org> Reviewed-by: Zi Yan <ziy@nvidia.com> Reviewed-by: Shakeel Butt <shakeelb@google.com> Acked-by: Michal Hocko <mhocko@suse.com> Cc: Hanjun Guo <guohanjun@huawei.com> Cc: Hugh Dickins <hughd@google.com> Cc: Kefeng Wang <wangkefeng.wang@huawei.com> Cc: "Kirill A. Shutemov" <kirill.shutemov@linux.intel.com> Cc: Nicholas Piggin <npiggin@gmail.com> Cc: Rui Xiang <rui.xiang@huawei.com> Cc: Tianhong Ding <dingtianhong@huawei.com> Cc: Weilong Chen <chenweilong@huawei.com> Cc: <stable@vger.kernel.org> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2021-03-13mm/memcg: rename mem_cgroup_split_huge_fixup to split_page_memcg and add ↵Zhou Guanghui
nr_pages argument Rename mem_cgroup_split_huge_fixup to split_page_memcg and explicitly pass in page number argument. In this way, the interface name is more common and can be used by potential users. In addition, the complete info(memcg and flag) of the memcg needs to be set to the tail pages. Link: https://lkml.kernel.org/r/20210304074053.65527-2-zhouguanghui1@huawei.com Signed-off-by: Zhou Guanghui <zhouguanghui1@huawei.com> Acked-by: Johannes Weiner <hannes@cmpxchg.org> Reviewed-by: Zi Yan <ziy@nvidia.com> Reviewed-by: Shakeel Butt <shakeelb@google.com> Acked-by: Michal Hocko <mhocko@suse.com> Cc: Hugh Dickins <hughd@google.com> Cc: "Kirill A. Shutemov" <kirill.shutemov@linux.intel.com> Cc: Nicholas Piggin <npiggin@gmail.com> Cc: Kefeng Wang <wangkefeng.wang@huawei.com> Cc: Hanjun Guo <guohanjun@huawei.com> Cc: Tianhong Ding <dingtianhong@huawei.com> Cc: Weilong Chen <chenweilong@huawei.com> Cc: Rui Xiang <rui.xiang@huawei.com> Cc: <stable@vger.kernel.org> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2021-03-13ia64: fix ptrace(PTRACE_SYSCALL_INFO_EXIT) signSergei Trofimovich
In https://bugs.gentoo.org/769614 Dmitry noticed that `ptrace(PTRACE_GET_SYSCALL_INFO)` does not return error sign properly. The bug is in mismatch between get/set errors: static inline long syscall_get_error(struct task_struct *task, struct pt_regs *regs) { return regs->r10 == -1 ? regs->r8:0; } static inline long syscall_get_return_value(struct task_struct *task, struct pt_regs *regs) { return regs->r8; } static inline void syscall_set_return_value(struct task_struct *task, struct pt_regs *regs, int error, long val) { if (error) { /* error < 0, but ia64 uses > 0 return value */ regs->r8 = -error; regs->r10 = -1; } else { regs->r8 = val; regs->r10 = 0; } } Tested on v5.10 on rx3600 machine (ia64 9040 CPU). Link: https://lkml.kernel.org/r/20210221002554.333076-2-slyfox@gentoo.org Link: https://bugs.gentoo.org/769614 Signed-off-by: Sergei Trofimovich <slyfox@gentoo.org> Reported-by: Dmitry V. Levin <ldv@altlinux.org> Reviewed-by: Dmitry V. Levin <ldv@altlinux.org> Cc: John Paul Adrian Glaubitz <glaubitz@physik.fu-berlin.de> Cc: Oleg Nesterov <oleg@redhat.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2021-03-13ia64: fix ia64_syscall_get_set_arguments() for break-based syscallsSergei Trofimovich
In https://bugs.gentoo.org/769614 Dmitry noticed that `ptrace(PTRACE_GET_SYSCALL_INFO)` does not work for syscalls called via glibc's syscall() wrapper. ia64 has two ways to call syscalls from userspace: via `break` and via `eps` instructions. The difference is in stack layout: 1. `eps` creates simple stack frame: no locals, in{0..7} == out{0..8} 2. `break` uses userspace stack frame: may be locals (glibc provides one), in{0..7} == out{0..8}. Both work fine in syscall handling cde itself. But `ptrace(PTRACE_GET_SYSCALL_INFO)` uses unwind mechanism to re-extract syscall arguments but it does not account for locals. The change always skips locals registers. It should not change `eps` path as kernel's handler already enforces locals=0 and fixes `break`. Tested on v5.10 on rx3600 machine (ia64 9040 CPU). Link: https://lkml.kernel.org/r/20210221002554.333076-1-slyfox@gentoo.org Link: https://bugs.gentoo.org/769614 Signed-off-by: Sergei Trofimovich <slyfox@gentoo.org> Reported-by: Dmitry V. Levin <ldv@altlinux.org> Cc: Oleg Nesterov <oleg@redhat.com> Cc: John Paul Adrian Glaubitz <glaubitz@physik.fu-berlin.de> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2021-03-13mm/userfaultfd: fix memory corruption due to writeprotectNadav Amit
Userfaultfd self-test fails occasionally, indicating a memory corruption. Analyzing this problem indicates that there is a real bug since mmap_lock is only taken for read in mwriteprotect_range() and defers flushes, and since there is insufficient consideration of concurrent deferred TLB flushes in wp_page_copy(). Although the PTE is flushed from the TLBs in wp_page_copy(), this flush takes place after the copy has already been performed, and therefore changes of the page are possible between the time of the copy and the time in which the PTE is flushed. To make matters worse, memory-unprotection using userfaultfd also poses a problem. Although memory unprotection is logically a promotion of PTE permissions, and therefore should not require a TLB flush, the current userrfaultfd code might actually cause a demotion of the architectural PTE permission: when userfaultfd_writeprotect() unprotects memory region, it unintentionally *clears* the RW-bit if it was already set. Note that this unprotecting a PTE that is not write-protected is a valid use-case: the userfaultfd monitor might ask to unprotect a region that holds both write-protected and write-unprotected PTEs. The scenario that happens in selftests/vm/userfaultfd is as follows: cpu0 cpu1 cpu2 ---- ---- ---- [ Writable PTE cached in TLB ] userfaultfd_writeprotect() [ write-*unprotect* ] mwriteprotect_range() mmap_read_lock() change_protection() change_protection_range() ... change_pte_range() [ *clear* “write”-bit ] [ defer TLB flushes ] [ page-fault ] ... wp_page_copy() cow_user_page() [ copy page ] [ write to old page ] ... set_pte_at_notify() A similar scenario can happen: cpu0 cpu1 cpu2 cpu3 ---- ---- ---- ---- [ Writable PTE cached in TLB ] userfaultfd_writeprotect() [ write-protect ] [ deferred TLB flush ] userfaultfd_writeprotect() [ write-unprotect ] [ deferred TLB flush] [ page-fault ] wp_page_copy() cow_user_page() [ copy page ] ... [ write to page ] set_pte_at_notify() This race exists since commit 292924b26024 ("userfaultfd: wp: apply _PAGE_UFFD_WP bit"). Yet, as Yu Zhao pointed, these races became apparent since commit 09854ba94c6a ("mm: do_wp_page() simplification") which made wp_page_copy() more likely to take place, specifically if page_count(page) > 1. To resolve the aforementioned races, check whether there are pending flushes on uffd-write-protected VMAs, and if there are, perform a flush before doing the COW. Further optimizations will follow to avoid during uffd-write-unprotect unnecassary PTE write-protection and TLB flushes. Link: https://lkml.kernel.org/r/20210304095423.3825684-1-namit@vmware.com Fixes: 09854ba94c6a ("mm: do_wp_page() simplification") Signed-off-by: Nadav Amit <namit@vmware.com> Suggested-by: Yu Zhao <yuzhao@google.com> Reviewed-by: Peter Xu <peterx@redhat.com> Tested-by: Peter Xu <peterx@redhat.com> Cc: Andrea Arcangeli <aarcange@redhat.com> Cc: Andy Lutomirski <luto@kernel.org> Cc: Pavel Emelyanov <xemul@openvz.org> Cc: Mike Kravetz <mike.kravetz@oracle.com> Cc: Mike Rapoport <rppt@linux.vnet.ibm.com> Cc: Minchan Kim <minchan@kernel.org> Cc: Will Deacon <will@kernel.org> Cc: Peter Zijlstra <peterz@infradead.org> Cc: <stable@vger.kernel.org> [5.9+] Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2021-03-13kasan: fix KASAN_STACK dependency for HW_TAGSAndrey Konovalov
There's a runtime failure when running HW_TAGS-enabled kernel built with GCC on hardware that doesn't support MTE. GCC-built kernels always have CONFIG_KASAN_STACK enabled, even though stack instrumentation isn't supported by HW_TAGS. Having that config enabled causes KASAN to issue MTE-only instructions to unpoison kernel stacks, which causes the failure. Fix the issue by disallowing CONFIG_KASAN_STACK when HW_TAGS is used. (The commit that introduced CONFIG_KASAN_HW_TAGS specified proper dependency for CONFIG_KASAN_STACK_ENABLE but not for CONFIG_KASAN_STACK.) Link: https://lkml.kernel.org/r/59e75426241dbb5611277758c8d4d6f5f9298dac.1615215441.git.andreyknvl@google.com Fixes: 6a63a63ff1ac ("kasan: introduce CONFIG_KASAN_HW_TAGS") Signed-off-by: Andrey Konovalov <andreyknvl@google.com> Reported-by: Catalin Marinas <catalin.marinas@arm.com> Cc: <stable@vger.kernel.org> Cc: Will Deacon <will.deacon@arm.com> Cc: Vincenzo Frascino <vincenzo.frascino@arm.com> Cc: Dmitry Vyukov <dvyukov@google.com> Cc: Andrey Ryabinin <aryabinin@virtuozzo.com> Cc: Alexander Potapenko <glider@google.com> Cc: Marco Elver <elver@google.com> Cc: Peter Collingbourne <pcc@google.com> Cc: Evgenii Stepanov <eugenis@google.com> Cc: Branislav Rankov <Branislav.Rankov@arm.com> Cc: Kevin Brodsky <kevin.brodsky@arm.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2021-03-13kasan, mm: fix crash with HW_TAGS and DEBUG_PAGEALLOCAndrey Konovalov
Currently, kasan_free_nondeferred_pages()->kasan_free_pages() is called after debug_pagealloc_unmap_pages(). This causes a crash when debug_pagealloc is enabled, as HW_TAGS KASAN can't set tags on an unmapped page. This patch puts kasan_free_nondeferred_pages() before debug_pagealloc_unmap_pages() and arch_free_page(), which can also make the page unavailable. Link: https://lkml.kernel.org/r/24cd7db274090f0e5bc3adcdc7399243668e3171.1614987311.git.andreyknvl@google.com Fixes: 94ab5b61ee16 ("kasan, arm64: enable CONFIG_KASAN_HW_TAGS") Signed-off-by: Andrey Konovalov <andreyknvl@google.com> Cc: Catalin Marinas <catalin.marinas@arm.com> Cc: Will Deacon <will.deacon@arm.com> Cc: Vincenzo Frascino <vincenzo.frascino@arm.com> Cc: Dmitry Vyukov <dvyukov@google.com> Cc: Andrey Ryabinin <aryabinin@virtuozzo.com> Cc: Alexander Potapenko <glider@google.com> Cc: Marco Elver <elver@google.com> Cc: Peter Collingbourne <pcc@google.com> Cc: Evgenii Stepanov <eugenis@google.com> Cc: Branislav Rankov <Branislav.Rankov@arm.com> Cc: Kevin Brodsky <kevin.brodsky@arm.com> Cc: Christoph Hellwig <hch@infradead.org> Cc: <stable@vger.kernel.org> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2021-03-13mm/madvise: replace ptrace attach requirement for process_madviseSuren Baghdasaryan
process_madvise currently requires ptrace attach capability. PTRACE_MODE_ATTACH gives one process complete control over another process. It effectively removes the security boundary between the two processes (in one direction). Granting ptrace attach capability even to a system process is considered dangerous since it creates an attack surface. This severely limits the usage of this API. The operations process_madvise can perform do not affect the correctness of the operation of the target process; they only affect where the data is physically located (and therefore, how fast it can be accessed). What we want is the ability for one process to influence another process in order to optimize performance across the entire system while leaving the security boundary intact. Replace PTRACE_MODE_ATTACH with a combination of PTRACE_MODE_READ and CAP_SYS_NICE. PTRACE_MODE_READ to prevent leaking ASLR metadata and CAP_SYS_NICE for influencing process performance. Link: https://lkml.kernel.org/r/20210303185807.2160264-1-surenb@google.com Signed-off-by: Suren Baghdasaryan <surenb@google.com> Reviewed-by: Kees Cook <keescook@chromium.org> Acked-by: Minchan Kim <minchan@kernel.org> Acked-by: David Rientjes <rientjes@google.com> Cc: Jann Horn <jannh@google.com> Cc: Jeff Vander Stoep <jeffv@google.com> Cc: Michal Hocko <mhocko@suse.com> Cc: Shakeel Butt <shakeelb@google.com> Cc: Tim Murray <timmurray@google.com> Cc: Florian Weimer <fweimer@redhat.com> Cc: Oleg Nesterov <oleg@redhat.com> Cc: James Morris <jmorris@namei.org> Cc: <stable@vger.kernel.org> [5.10+] Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2021-03-13include/linux/sched/mm.h: use rcu_dereference in in_vfork()Matthew Wilcox (Oracle)
Fix a sparse warning by using rcu_dereference(). Technically this is a bug and a sufficiently aggressive compiler could reload the `real_parent' pointer outside the protection of the rcu lock (and access freed memory), but I think it's pretty unlikely to happen. Link: https://lkml.kernel.org/r/20210221194207.1351703-1-willy@infradead.org Fixes: b18dc5f291c0 ("mm, oom: skip vforked tasks from being selected") Signed-off-by: Matthew Wilcox (Oracle) <willy@infradead.org> Reviewed-by: Miaohe Lin <linmiaohe@huawei.com> Acked-by: Michal Hocko <mhocko@suse.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>