linux_dsm_epyc7002/arch/x86
Wanpeng Li 9a6e7c3981 KVM: async_pf: Fix #DF due to inject "Page not Present" and "Page Ready" exceptions simultaneously
qemu-system-x86-8600  [004] d..1  7205.687530: kvm_entry: vcpu 2
qemu-system-x86-8600  [004] ....  7205.687532: kvm_exit: reason EXCEPTION_NMI rip 0xffffffffa921297d info ffffeb2c0e44e018 80000b0e
qemu-system-x86-8600  [004] ....  7205.687532: kvm_page_fault: address ffffeb2c0e44e018 error_code 0
qemu-system-x86-8600  [004] ....  7205.687620: kvm_try_async_get_page: gva = 0xffffeb2c0e44e018, gfn = 0x427e4e
qemu-system-x86-8600  [004] .N..  7205.687628: kvm_async_pf_not_present: token 0x8b002 gva 0xffffeb2c0e44e018
    kworker/4:2-7814  [004] ....  7205.687655: kvm_async_pf_completed: gva 0xffffeb2c0e44e018 address 0x7fcc30c4e000
qemu-system-x86-8600  [004] ....  7205.687703: kvm_async_pf_ready: token 0x8b002 gva 0xffffeb2c0e44e018
qemu-system-x86-8600  [004] d..1  7205.687711: kvm_entry: vcpu 2

After running some memory intensive workload in guest, I catch the kworker
which completes the GUP too quickly, and queues an "Page Ready" #PF exception
after the "Page not Present" exception before the next vmentry as the above
trace which will result in #DF injected to guest.

This patch fixes it by clearing the queue for "Page not Present" if "Page Ready"
occurs before the next vmentry since the GUP has already got the required page
and shadow page table has already been fixed by "Page Ready" handler.

Cc: Paolo Bonzini <pbonzini@redhat.com>
Cc: Radim Krčmář <rkrcmar@redhat.com>
Signed-off-by: Wanpeng Li <wanpeng.li@hotmail.com>
Fixes: 7c90705bf2 ("KVM: Inject asynchronous page fault into a PV guest if page is swapped out.")
[Changed indentation and added clearing of injected. - Radim]
Signed-off-by: Radim Krčmář <rkrcmar@redhat.com>
2017-09-14 18:43:43 +02:00
..
boot Merge branch 'efi-core-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip 2017-09-07 09:42:35 -07:00
configs Merge branch 'x86/urgent' into x86/asm, to pick up fixes 2017-08-10 13:14:15 +02:00
crypto Merge git://git.kernel.org/pub/scm/linux/kernel/git/herbert/crypto-2.6 2017-08-22 14:53:32 +08:00
entry Merge branch 'x86-apic-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip 2017-09-04 17:43:56 -07:00
events Merge branch 'x86-cache-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip 2017-09-04 13:56:37 -07:00
hyperv tracing/hyper-v: Trace hyperv_mmu_flush_tlb_others() 2017-08-31 14:20:37 +02:00
ia32 x86/asm/32: Remove a bunch of '& 0xffff' from pt_regs segment reads 2017-07-30 12:04:41 +02:00
include KVM: Add struct kvm_vcpu pointer parameter to get_enable_apicv() 2017-09-13 18:29:06 +02:00
kernel Merge branch 'x86-platform-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip 2017-09-07 09:25:15 -07:00
kvm KVM: async_pf: Fix #DF due to inject "Page not Present" and "Page Ready" exceptions simultaneously 2017-09-14 18:43:43 +02:00
lib x86/boot: Add early cmdline parsing for options with arguments 2017-07-18 11:38:06 +02:00
math-emu Merge branch 'x86-apic-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip 2017-09-04 17:43:56 -07:00
mm x86/mm: Reinitialize TLB state on hotplug and resume 2017-09-06 20:12:57 -07:00
net x86: bpf_jit: small optimization in emit_bpf_tail_call() 2017-08-31 11:57:37 -07:00
oprofile
pci Merge branch 'x86/mm' into x86/platform, to pick up TLB flush dependency 2017-08-31 14:20:06 +02:00
platform Merge branch 'efi-core-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip 2017-09-07 09:42:35 -07:00
power x86/mm: Reinitialize TLB state on hotplug and resume 2017-09-06 20:12:57 -07:00
purgatory
ras
realmode x86/boot/realmode: Check for memory encryption on the APs 2017-07-18 11:38:04 +02:00
tools
um um: Fix check for _xstate for older hosts 2017-08-24 21:52:28 +02:00
video
xen xen: fixes and features for 4.14 2017-09-07 10:24:21 -07:00
.gitignore
Kbuild Merge branch 'x86-platform-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip 2017-09-07 09:25:15 -07:00
Kconfig x86,mpx: make mpx depend on x86-64 to free up VMA flag 2017-09-06 17:27:30 -07:00
Kconfig.cpu
Kconfig.debug Merge branch 'x86/asm' into locking/core 2017-08-18 10:29:54 +02:00
Makefile x86/build: Use cc-option to validate stack alignment parameter 2017-08-21 09:53:15 +02:00
Makefile_32.cpu
Makefile.um