Hi all, While stress-testing my arm64 stage-2 page-table rewrite [1], I ran into a sleeping while atomic BUG() during OOM that I can reproduce with mainline. The problem is that the arm64 page-table code periodically calls cond_resched_lock() when unmapping the stage-2 page-tables, but in the case of OOM, this occurs in atomic context. These couple of patches (based on 5.8) propagate the flags from the MMU notifier range structure, which in turn indicate whether or not blocking is permitted. Cheers, Will [1] https://android-kvm.googlesource.com/linux/+/refs/heads/topic/pgtable Cc: Marc Zyngier <maz@xxxxxxxxxx> Cc: Suzuki K Poulose <suzuki.poulose@xxxxxxx> Cc: James Morse <james.morse@xxxxxxx> Cc: Thomas Bogendoerfer <tsbogend@xxxxxxxxxxxxxxxx> Cc: Paul Mackerras <paulus@xxxxxxxxxx> Cc: Paolo Bonzini <pbonzini@xxxxxxxxxx> Cc: Sean Christopherson <sean.j.christopherson@xxxxxxxxx> --->8 Will Deacon (2): KVM: Pass MMU notifier range flags to kvm_unmap_hva_range() KVM: arm64: Only reschedule if MMU_NOTIFIER_RANGE_BLOCKABLE is not set arch/arm64/include/asm/kvm_host.h | 2 +- arch/arm64/kvm/mmu.c | 19 ++++++++++++++----- arch/mips/include/asm/kvm_host.h | 2 +- arch/mips/kvm/mmu.c | 3 ++- arch/powerpc/include/asm/kvm_host.h | 3 ++- arch/powerpc/kvm/book3s.c | 3 ++- arch/powerpc/kvm/e500_mmu_host.c | 3 ++- arch/x86/include/asm/kvm_host.h | 3 ++- arch/x86/kvm/mmu/mmu.c | 3 ++- virt/kvm/kvm_main.c | 3 ++- 10 files changed, 30 insertions(+), 14 deletions(-) -- 2.28.0.236.gb10cc79966-goog _______________________________________________ kvmarm mailing list kvmarm@xxxxxxxxxxxxxxxxxxxxx https://lists.cs.columbia.edu/mailman/listinfo/kvmarm
