[PATCH 1/2] KVM: Pass MMU notifier range flags to kvm_unmap_hva_range()

[PATCH 1/2] KVM: Pass MMU notifier range flags to kvm_unmap_hva_range()

[Will Deacon]

The 'flags' field of 'struct mmu_notifier_range' is used to indicate
whether invalidate_range_{start,end}() are permitted to block. In the
case of kvm_mmu_notifier_invalidate_range_start(), this field is not
forwarded on to the architecture-specific implementation of
kvm_unmap_hva_range() and therefore the backend cannot sensibly decide
whether or not to block.

Add an extra 'flags' parameter to kvm_unmap_hva_range() so that
architectures are aware as to whether or not they are permitted to block.

Cc: <stable@vger.kernel.org>
Cc: Marc Zyngier <maz@kernel.org>
Cc: Suzuki K Poulose <suzuki.poulose@arm.com>
Cc: James Morse <james.morse@arm.com>
Signed-off-by: Will Deacon <will@kernel.org>
---
 arch/arm64/include/asm/kvm_host.h   | 2 +-
 arch/arm64/kvm/mmu.c                | 2 +-
 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, 17 insertions(+), 10 deletions(-)

diff --git a/arch/arm64/include/asm/kvm_host.h b/arch/arm64/include/asm/kvm_host.h
index e21d4a01372f..759d62343e1d 100644
--- a/arch/arm64/include/asm/kvm_host.h
+++ b/arch/arm64/include/asm/kvm_host.h
@@ -443,7 +443,7 @@ int __kvm_arm_vcpu_set_events(struct kvm_vcpu *vcpu,
 
 #define KVM_ARCH_WANT_MMU_NOTIFIER
 int kvm_unmap_hva_range(struct kvm *kvm,
-			unsigned long start, unsigned long end);
+			unsigned long start, unsigned long end, unsigned flags);
 int kvm_set_spte_hva(struct kvm *kvm, unsigned long hva, pte_t pte);
 int kvm_age_hva(struct kvm *kvm, unsigned long start, unsigned long end);
 int kvm_test_age_hva(struct kvm *kvm, unsigned long hva);
diff --git a/arch/arm64/kvm/mmu.c b/arch/arm64/kvm/mmu.c
index 31058e6e7c2a..5f6b35c33618 100644
--- a/arch/arm64/kvm/mmu.c
+++ b/arch/arm64/kvm/mmu.c
@@ -2203,7 +2203,7 @@ static int kvm_unmap_hva_handler(struct kvm *kvm, gpa_t gpa, u64 size, void *dat
 }
 
 int kvm_unmap_hva_range(struct kvm *kvm,
-			unsigned long start, unsigned long end)
+			unsigned long start, unsigned long end, unsigned flags)
 {
 	if (!kvm->arch.pgd)
 		return 0;
diff --git a/arch/mips/include/asm/kvm_host.h b/arch/mips/include/asm/kvm_host.h
index 363e7a89d173..ef1d25d49ec8 100644
--- a/arch/mips/include/asm/kvm_host.h
+++ b/arch/mips/include/asm/kvm_host.h
@@ -981,7 +981,7 @@ enum kvm_mips_fault_result kvm_trap_emul_gva_fault(struct kvm_vcpu *vcpu,
 
 #define KVM_ARCH_WANT_MMU_NOTIFIER
 int kvm_unmap_hva_range(struct kvm *kvm,
-			unsigned long start, unsigned long end);
+			unsigned long start, unsigned long end, unsigned flags);
 int kvm_set_spte_hva(struct kvm *kvm, unsigned long hva, pte_t pte);
 int kvm_age_hva(struct kvm *kvm, unsigned long start, unsigned long end);
 int kvm_test_age_hva(struct kvm *kvm, unsigned long hva);
diff --git a/arch/mips/kvm/mmu.c b/arch/mips/kvm/mmu.c
index 49bd160f4d85..0783ac9b3240 100644
--- a/arch/mips/kvm/mmu.c
+++ b/arch/mips/kvm/mmu.c
@@ -518,7 +518,8 @@ static int kvm_unmap_hva_handler(struct kvm *kvm, gfn_t gfn, gfn_t gfn_end,
 	return 1;
 }
 
-int kvm_unmap_hva_range(struct kvm *kvm, unsigned long start, unsigned long end)
+int kvm_unmap_hva_range(struct kvm *kvm, unsigned long start, unsigned long end,
+			unsigned flags)
 {
 	handle_hva_to_gpa(kvm, start, end, &kvm_unmap_hva_handler, NULL);
 
diff --git a/arch/powerpc/include/asm/kvm_host.h b/arch/powerpc/include/asm/kvm_host.h
index 7e2d061d0445..bccf0ba2da2e 100644
--- a/arch/powerpc/include/asm/kvm_host.h
+++ b/arch/powerpc/include/asm/kvm_host.h
@@ -58,7 +58,8 @@
 #define KVM_ARCH_WANT_MMU_NOTIFIER
 
 extern int kvm_unmap_hva_range(struct kvm *kvm,
-			       unsigned long start, unsigned long end);
+			       unsigned long start, unsigned long end,
+			       unsigned flags);
 extern int kvm_age_hva(struct kvm *kvm, unsigned long start, unsigned long end);
 extern int kvm_test_age_hva(struct kvm *kvm, unsigned long hva);
 extern int kvm_set_spte_hva(struct kvm *kvm, unsigned long hva, pte_t pte);
diff --git a/arch/powerpc/kvm/book3s.c b/arch/powerpc/kvm/book3s.c
index 41fedec69ac3..49db50d1db04 100644
--- a/arch/powerpc/kvm/book3s.c
+++ b/arch/powerpc/kvm/book3s.c
@@ -834,7 +834,8 @@ void kvmppc_core_commit_memory_region(struct kvm *kvm,
 	kvm->arch.kvm_ops->commit_memory_region(kvm, mem, old, new, change);
 }
 
-int kvm_unmap_hva_range(struct kvm *kvm, unsigned long start, unsigned long end)
+int kvm_unmap_hva_range(struct kvm *kvm, unsigned long start, unsigned long end,
+			unsigned flags)
 {
 	return kvm->arch.kvm_ops->unmap_hva_range(kvm, start, end);
 }
diff --git a/arch/powerpc/kvm/e500_mmu_host.c b/arch/powerpc/kvm/e500_mmu_host.c
index d6c1069e9954..ed0c9c43d0cf 100644
--- a/arch/powerpc/kvm/e500_mmu_host.c
+++ b/arch/powerpc/kvm/e500_mmu_host.c
@@ -734,7 +734,8 @@ static int kvm_unmap_hva(struct kvm *kvm, unsigned long hva)
 	return 0;
 }
 
-int kvm_unmap_hva_range(struct kvm *kvm, unsigned long start, unsigned long end)
+int kvm_unmap_hva_range(struct kvm *kvm, unsigned long start, unsigned long end,
+			unsigned flags)
 {
 	/* kvm_unmap_hva flushes everything anyways */
 	kvm_unmap_hva(kvm, start);
diff --git a/arch/x86/include/asm/kvm_host.h b/arch/x86/include/asm/kvm_host.h
index be5363b21540..c6908a3d551e 100644
--- a/arch/x86/include/asm/kvm_host.h
+++ b/arch/x86/include/asm/kvm_host.h
@@ -1641,7 +1641,8 @@ asmlinkage void kvm_spurious_fault(void);
 	_ASM_EXTABLE(666b, 667b)
 
 #define KVM_ARCH_WANT_MMU_NOTIFIER
-int kvm_unmap_hva_range(struct kvm *kvm, unsigned long start, unsigned long end);
+int kvm_unmap_hva_range(struct kvm *kvm, unsigned long start, unsigned long end,
+			unsigned flags);
 int kvm_age_hva(struct kvm *kvm, unsigned long start, unsigned long end);
 int kvm_test_age_hva(struct kvm *kvm, unsigned long hva);
 int kvm_set_spte_hva(struct kvm *kvm, unsigned long hva, pte_t pte);
diff --git a/arch/x86/kvm/mmu/mmu.c b/arch/x86/kvm/mmu/mmu.c
index 6d6a0ae7800c..9516a958e780 100644
--- a/arch/x86/kvm/mmu/mmu.c
+++ b/arch/x86/kvm/mmu/mmu.c
@@ -1971,7 +1971,8 @@ static int kvm_handle_hva(struct kvm *kvm, unsigned long hva,
 	return kvm_handle_hva_range(kvm, hva, hva + 1, data, handler);
 }
 
-int kvm_unmap_hva_range(struct kvm *kvm, unsigned long start, unsigned long end)
+int kvm_unmap_hva_range(struct kvm *kvm, unsigned long start, unsigned long end,
+			unsigned flags)
 {
 	return kvm_handle_hva_range(kvm, start, end, 0, kvm_unmap_rmapp);
 }
diff --git a/virt/kvm/kvm_main.c b/virt/kvm/kvm_main.c
index 0a68c9d3d3ab..9e925675a886 100644
--- a/virt/kvm/kvm_main.c
+++ b/virt/kvm/kvm_main.c
@@ -427,7 +427,8 @@ static int kvm_mmu_notifier_invalidate_range_start(struct mmu_notifier *mn,
 	 * count is also read inside the mmu_lock critical section.
 	 */
 	kvm->mmu_notifier_count++;
-	need_tlb_flush = kvm_unmap_hva_range(kvm, range->start, range->end);
+	need_tlb_flush = kvm_unmap_hva_range(kvm, range->start, range->end,
+					     range->flags);
 	need_tlb_flush |= kvm->tlbs_dirty;
 	/* we've to flush the tlb before the pages can be freed */
 	if (need_tlb_flush)
-- 
2.28.0.236.gb10cc79966-goog

[PATCH 2/2] KVM: arm64: Only reschedule if MMU_NOTIFIER_RANGE_BLOCKABLE is not set

[Will Deacon]

When an MMU notifier call results in unmapping a range that spans multiple
PGDs, we end up calling into cond_resched_lock() when crossing a PGD boundary,
since this avoids running into RCU stalls during VM teardown. Unfortunately,
if the VM is destroyed as a result of OOM, then blocking is not permitted
and the call to the scheduler triggers the following BUG():

 | BUG: sleeping function called from invalid context at arch/arm64/kvm/mmu.c:394
 | in_atomic(): 1, irqs_disabled(): 0, non_block: 1, pid: 36, name: oom_reaper
 | INFO: lockdep is turned off.
 | CPU: 3 PID: 36 Comm: oom_reaper Not tainted 5.8.0 #1
 | Hardware name: QEMU QEMU Virtual Machine, BIOS 0.0.0 02/06/2015
 | Call trace:
 |  dump_backtrace+0x0/0x284
 |  show_stack+0x1c/0x28
 |  dump_stack+0xf0/0x1a4
 |  ___might_sleep+0x2bc/0x2cc
 |  unmap_stage2_range+0x160/0x1ac
 |  kvm_unmap_hva_range+0x1a0/0x1c8
 |  kvm_mmu_notifier_invalidate_range_start+0x8c/0xf8
 |  __mmu_notifier_invalidate_range_start+0x218/0x31c
 |  mmu_notifier_invalidate_range_start_nonblock+0x78/0xb0
 |  __oom_reap_task_mm+0x128/0x268
 |  oom_reap_task+0xac/0x298
 |  oom_reaper+0x178/0x17c
 |  kthread+0x1e4/0x1fc
 |  ret_from_fork+0x10/0x30

Use the new 'flags' argument to kvm_unmap_hva_range() to ensure that we
only reschedule if MMU_NOTIFIER_RANGE_BLOCKABLE is set in the notifier
flags.

Cc: <stable@vger.kernel.org>
Fixes: 8b3405e345b5 ("kvm: arm/arm64: Fix locking for kvm_free_stage2_pgd")
Cc: Marc Zyngier <maz@kernel.org>
Cc: Suzuki K Poulose <suzuki.poulose@arm.com>
Cc: James Morse <james.morse@arm.com>
Signed-off-by: Will Deacon <will@kernel.org>
---
 arch/arm64/kvm/mmu.c | 17 +++++++++++++----
 1 file changed, 13 insertions(+), 4 deletions(-)

diff --git a/arch/arm64/kvm/mmu.c b/arch/arm64/kvm/mmu.c
index 5f6b35c33618..bd47f06739d6 100644
--- a/arch/arm64/kvm/mmu.c
+++ b/arch/arm64/kvm/mmu.c
@@ -365,7 +365,8 @@ static void unmap_stage2_p4ds(struct kvm *kvm, pgd_t *pgd,
  * destroying the VM), otherwise another faulting VCPU may come in and mess
  * with things behind our backs.
  */
-static void unmap_stage2_range(struct kvm *kvm, phys_addr_t start, u64 size)
+static void __unmap_stage2_range(struct kvm *kvm, phys_addr_t start, u64 size,
+				 bool may_block)
 {
 	pgd_t *pgd;
 	phys_addr_t addr = start, end = start + size;
@@ -390,11 +391,16 @@ static void unmap_stage2_range(struct kvm *kvm, phys_addr_t start, u64 size)
 		 * If the range is too large, release the kvm->mmu_lock
 		 * to prevent starvation and lockup detector warnings.
 		 */
-		if (next != end)
+		if (may_block && next != end)
 			cond_resched_lock(&kvm->mmu_lock);
 	} while (pgd++, addr = next, addr != end);
 }
 
+static void unmap_stage2_range(struct kvm *kvm, phys_addr_t start, u64 size)
+{
+	__unmap_stage2_range(kvm, start, size, true);
+}
+
 static void stage2_flush_ptes(struct kvm *kvm, pmd_t *pmd,
 			      phys_addr_t addr, phys_addr_t end)
 {
@@ -2198,7 +2204,10 @@ static int handle_hva_to_gpa(struct kvm *kvm,
 
 static int kvm_unmap_hva_handler(struct kvm *kvm, gpa_t gpa, u64 size, void *data)
 {
-	unmap_stage2_range(kvm, gpa, size);
+	unsigned flags = *(unsigned *)data;
+	bool may_block = flags & MMU_NOTIFIER_RANGE_BLOCKABLE;
+
+	__unmap_stage2_range(kvm, gpa, size, may_block);
 	return 0;
 }
 
@@ -2209,7 +2218,7 @@ int kvm_unmap_hva_range(struct kvm *kvm,
 		return 0;
 
 	trace_kvm_unmap_hva_range(start, end);
-	handle_hva_to_gpa(kvm, start, end, &kvm_unmap_hva_handler, NULL);
+	handle_hva_to_gpa(kvm, start, end, &kvm_unmap_hva_handler, &flags);
 	return 0;
 }
 
-- 
2.28.0.236.gb10cc79966-goog

Re: [PATCH 2/2] KVM: arm64: Only reschedule if MMU_NOTIFIER_RANGE_BLOCKABLE is not set

[Suzuki K Poulose]

On 08/11/2020 11:27 AM, Will Deacon wrote:
> When an MMU notifier call results in unmapping a range that spans multiple
> PGDs, we end up calling into cond_resched_lock() when crossing a PGD boundary,
> since this avoids running into RCU stalls during VM teardown. Unfortunately,
> if the VM is destroyed as a result of OOM, then blocking is not permitted
> and the call to the scheduler triggers the following BUG():
> 
>   | BUG: sleeping function called from invalid context at arch/arm64/kvm/mmu.c:394
>   | in_atomic(): 1, irqs_disabled(): 0, non_block: 1, pid: 36, name: oom_reaper
>   | INFO: lockdep is turned off.
>   | CPU: 3 PID: 36 Comm: oom_reaper Not tainted 5.8.0 #1
>   | Hardware name: QEMU QEMU Virtual Machine, BIOS 0.0.0 02/06/2015
>   | Call trace:
>   |  dump_backtrace+0x0/0x284
>   |  show_stack+0x1c/0x28
>   |  dump_stack+0xf0/0x1a4
>   |  ___might_sleep+0x2bc/0x2cc
>   |  unmap_stage2_range+0x160/0x1ac
>   |  kvm_unmap_hva_range+0x1a0/0x1c8
>   |  kvm_mmu_notifier_invalidate_range_start+0x8c/0xf8
>   |  __mmu_notifier_invalidate_range_start+0x218/0x31c
>   |  mmu_notifier_invalidate_range_start_nonblock+0x78/0xb0
>   |  __oom_reap_task_mm+0x128/0x268
>   |  oom_reap_task+0xac/0x298
>   |  oom_reaper+0x178/0x17c
>   |  kthread+0x1e4/0x1fc
>   |  ret_from_fork+0x10/0x30
> 
> Use the new 'flags' argument to kvm_unmap_hva_range() to ensure that we
> only reschedule if MMU_NOTIFIER_RANGE_BLOCKABLE is set in the notifier
> flags.
> 
> Cc: <stable@vger.kernel.org>
> Fixes: 8b3405e345b5 ("kvm: arm/arm64: Fix locking for kvm_free_stage2_pgd")
> Cc: Marc Zyngier <maz@kernel.org>
> Cc: Suzuki K Poulose <suzuki.poulose@arm.com>
> Cc: James Morse <james.morse@arm.com>
> Signed-off-by: Will Deacon <will@kernel.org>
> ---

Reviewed-by: Suzuki K Poulose <suzuki.poulose@arm.com>

Re: [PATCH 1/2] KVM: Pass MMU notifier range flags to kvm_unmap_hva_range()

[Sasha Levin]

Hi

[This is an automated email]

This commit has been processed because it contains a -stable tag.
The stable tag indicates that it's relevant for the following trees: all

The bot has tested the following trees: v5.8.1, v5.7.15, v5.4.58, v4.19.139, v4.14.193, v4.9.232, v4.4.232.

v5.8.1: Build OK!
v5.7.15: Build OK!
v5.4.58: Build OK!
v4.19.139: Failed to apply! Possible dependencies:
    18fc7bf8e041 ("arm64: KVM: Allow for direct call of HYP functions when using VHE")
    208243c752a7 ("KVM: arm64: Move hyp-init.S to nVHE")
    25357de01b95 ("KVM: arm64: Clean up kvm makefiles")
    33e45234987e ("arm64: initialize and switch ptrauth kernel keys")
    396244692232 ("arm64: preempt: Provide our own implementation of asm/preempt.h")
    3f58bf634555 ("KVM: arm/arm64: Share common code in user_mem_abort()")
    6396b852e46e ("KVM: arm/arm64: Re-factor setting the Stage 2 entry to exec on fault")
    748c0e312fce ("KVM: Make kvm_set_spte_hva() return int")
    750319756256 ("arm64: add basic pointer authentication support")
    7621712918ad ("KVM: arm64: Add build rules for separate VHE/nVHE object files")
    7aa8d1464165 ("arm/arm64: KVM: Introduce kvm_call_hyp_ret()")
    86d0dd34eaff ("arm64: cpufeature: add feature for CRC32 instructions")
    90776dd1c427 ("arm64/efi: Move variable assignments after SECTIONS")
    95b861a4a6d9 ("arm64: arch_timer: Add workaround for ARM erratum 1188873")
    a0e50aa3f4a8 ("KVM: arm64: Factor out stage 2 page table data from struct kvm")
    b877e9849d41 ("KVM: arm64: Build hyp-entry.S separately for VHE/nVHE")
    bd4fb6d270bc ("arm64: Add support for SB barrier and patch in over DSB; ISB sequences")
    be1298425665 ("arm64: install user ptrauth keys at kernel exit time")
    d82755b2e781 ("KVM: arm64: Kill off CONFIG_KVM_ARM_HOST")
    f50b6f6ae131 ("KVM: arm64: Handle calls to prefixed hyp functions")
    f56063c51f9f ("arm64: add image head flag definitions")
    f8df73388ee2 ("KVM: arm/arm64: Introduce helpers to manipulate page table entries")

v4.14.193: Failed to apply! Possible dependencies:
    0db9dd8a0fbd ("KVM: arm/arm64: Stop using the kernel's {pmd,pud,pgd}_populate helpers")
    17ab9d57deba ("KVM: arm/arm64: Drop vcpu parameter from guest cache maintenance operartions")
    3f58bf634555 ("KVM: arm/arm64: Share common code in user_mem_abort()")
    6396b852e46e ("KVM: arm/arm64: Re-factor setting the Stage 2 entry to exec on fault")
    694556d54f35 ("KVM: arm/arm64: Clean dcache to PoC when changing PTE due to CoW")
    748c0e312fce ("KVM: Make kvm_set_spte_hva() return int")
    88dc25e8ea7c ("KVM: arm/arm64: Consolidate page-table accessors")
    91c703e0382a ("arm: KVM: Add optimized PIPT icache flushing")
    a15f693935a9 ("KVM: arm/arm64: Split dcache/icache flushing")
    a9c0e12ebee5 ("KVM: arm/arm64: Only clean the dcache on translation fault")
    d0e22b4ac3ba ("KVM: arm/arm64: Limit icache invalidation to prefetch aborts")
    f8df73388ee2 ("KVM: arm/arm64: Introduce helpers to manipulate page table entries")

v4.9.232: Failed to apply! Possible dependencies:
    1534b3964901 ("KVM: MIPS/MMU: Simplify ASID restoration")
    1581ff3dbf69 ("KVM: MIPS/MMU: Move preempt/ASID handling to implementation")
    1880afd6057f ("KVM: MIPS/T&E: Add lockless GVA access helpers")
    411740f5422a ("KVM: MIPS/MMU: Implement KVM_CAP_SYNC_MMU")
    748c0e312fce ("KVM: Make kvm_set_spte_hva() return int")
    91cdee5710d5 ("KVM: MIPS/T&E: Restore host asid on return to host")
    a2c046e40ff1 ("KVM: MIPS: Add vcpu_run() & vcpu_reenter() callbacks")
    a31b50d741bd ("KVM: MIPS/MMU: Invalidate GVA PTs on ASID changes")
    a60b8438bdba ("KVM: MIPS: Convert get/set_regs -> vcpu_load/put")
    a7ebb2e410f8 ("KVM: MIPS/T&E: active_mm = init_mm in guest context")
    aba8592950f1 ("KVM: MIPS/MMU: Invalidate stale GVA PTEs on TLBW")
    c550d53934d8 ("KVM: MIPS: Remove duplicated ASIDs from vcpu")

v4.4.232: Failed to apply! Possible dependencies:
    16d100db245a ("MIPS: Move Cause.ExcCode trap codes to mipsregs.h")
    1880afd6057f ("KVM: MIPS/T&E: Add lockless GVA access helpers")
    19d194c62b25 ("MIPS: KVM: Simplify TLB_* macros")
    411740f5422a ("KVM: MIPS/MMU: Implement KVM_CAP_SYNC_MMU")
    748c0e312fce ("KVM: Make kvm_set_spte_hva() return int")
    8cffd1974851 ("MIPS: KVM: Convert code to kernel sized types")
    9fbfb06a4065 ("MIPS: KVM: Arrayify struct kvm_mips_tlb::tlb_lo*")
    ba049e93aef7 ("kvm: rename pfn_t to kvm_pfn_t")
    bdb7ed8608f8 ("MIPS: KVM: Convert headers to kernel sized types")
    ca64c2beecd4 ("MIPS: KVM: Abstract guest ASID mask")
    caa1faa7aba6 ("MIPS: KVM: Trivial whitespace and style fixes")


NOTE: The patch will not be queued to stable trees until it is upstream.

How should we proceed with this patch?

-- 
Thanks
Sasha

Re: [PATCH 1/2] KVM: Pass MMU notifier range flags to kvm_unmap_hva_range()

[Sasha Levin]

Hi

[This is an automated email]

This commit has been processed because it contains a -stable tag.
The stable tag indicates that it's relevant for the following trees: all

The bot has tested the following trees: v5.8.2, v5.7.16, v5.4.59, v4.19.140, v4.14.193, v4.9.232, v4.4.232.

v5.8.2: Build OK!
v5.7.16: Build OK!
v5.4.59: Build OK!
v4.19.140: Failed to apply! Possible dependencies:
    18fc7bf8e041 ("arm64: KVM: Allow for direct call of HYP functions when using VHE")
    208243c752a7 ("KVM: arm64: Move hyp-init.S to nVHE")
    25357de01b95 ("KVM: arm64: Clean up kvm makefiles")
    33e45234987e ("arm64: initialize and switch ptrauth kernel keys")
    396244692232 ("arm64: preempt: Provide our own implementation of asm/preempt.h")
    3f58bf634555 ("KVM: arm/arm64: Share common code in user_mem_abort()")
    6396b852e46e ("KVM: arm/arm64: Re-factor setting the Stage 2 entry to exec on fault")
    748c0e312fce ("KVM: Make kvm_set_spte_hva() return int")
    750319756256 ("arm64: add basic pointer authentication support")
    7621712918ad ("KVM: arm64: Add build rules for separate VHE/nVHE object files")
    7aa8d1464165 ("arm/arm64: KVM: Introduce kvm_call_hyp_ret()")
    86d0dd34eaff ("arm64: cpufeature: add feature for CRC32 instructions")
    90776dd1c427 ("arm64/efi: Move variable assignments after SECTIONS")
    95b861a4a6d9 ("arm64: arch_timer: Add workaround for ARM erratum 1188873")
    a0e50aa3f4a8 ("KVM: arm64: Factor out stage 2 page table data from struct kvm")
    b877e9849d41 ("KVM: arm64: Build hyp-entry.S separately for VHE/nVHE")
    bd4fb6d270bc ("arm64: Add support for SB barrier and patch in over DSB; ISB sequences")
    be1298425665 ("arm64: install user ptrauth keys at kernel exit time")
    d82755b2e781 ("KVM: arm64: Kill off CONFIG_KVM_ARM_HOST")
    f50b6f6ae131 ("KVM: arm64: Handle calls to prefixed hyp functions")
    f56063c51f9f ("arm64: add image head flag definitions")
    f8df73388ee2 ("KVM: arm/arm64: Introduce helpers to manipulate page table entries")

v4.14.193: Failed to apply! Possible dependencies:
    0db9dd8a0fbd ("KVM: arm/arm64: Stop using the kernel's {pmd,pud,pgd}_populate helpers")
    17ab9d57deba ("KVM: arm/arm64: Drop vcpu parameter from guest cache maintenance operartions")
    3f58bf634555 ("KVM: arm/arm64: Share common code in user_mem_abort()")
    6396b852e46e ("KVM: arm/arm64: Re-factor setting the Stage 2 entry to exec on fault")
    694556d54f35 ("KVM: arm/arm64: Clean dcache to PoC when changing PTE due to CoW")
    748c0e312fce ("KVM: Make kvm_set_spte_hva() return int")
    88dc25e8ea7c ("KVM: arm/arm64: Consolidate page-table accessors")
    91c703e0382a ("arm: KVM: Add optimized PIPT icache flushing")
    a15f693935a9 ("KVM: arm/arm64: Split dcache/icache flushing")
    a9c0e12ebee5 ("KVM: arm/arm64: Only clean the dcache on translation fault")
    d0e22b4ac3ba ("KVM: arm/arm64: Limit icache invalidation to prefetch aborts")
    f8df73388ee2 ("KVM: arm/arm64: Introduce helpers to manipulate page table entries")

v4.9.232: Failed to apply! Possible dependencies:
    1534b3964901 ("KVM: MIPS/MMU: Simplify ASID restoration")
    1581ff3dbf69 ("KVM: MIPS/MMU: Move preempt/ASID handling to implementation")
    1880afd6057f ("KVM: MIPS/T&E: Add lockless GVA access helpers")
    411740f5422a ("KVM: MIPS/MMU: Implement KVM_CAP_SYNC_MMU")
    748c0e312fce ("KVM: Make kvm_set_spte_hva() return int")
    91cdee5710d5 ("KVM: MIPS/T&E: Restore host asid on return to host")
    a2c046e40ff1 ("KVM: MIPS: Add vcpu_run() & vcpu_reenter() callbacks")
    a31b50d741bd ("KVM: MIPS/MMU: Invalidate GVA PTs on ASID changes")
    a60b8438bdba ("KVM: MIPS: Convert get/set_regs -> vcpu_load/put")
    a7ebb2e410f8 ("KVM: MIPS/T&E: active_mm = init_mm in guest context")
    aba8592950f1 ("KVM: MIPS/MMU: Invalidate stale GVA PTEs on TLBW")
    c550d53934d8 ("KVM: MIPS: Remove duplicated ASIDs from vcpu")

v4.4.232: Failed to apply! Possible dependencies:
    16d100db245a ("MIPS: Move Cause.ExcCode trap codes to mipsregs.h")
    1880afd6057f ("KVM: MIPS/T&E: Add lockless GVA access helpers")
    19d194c62b25 ("MIPS: KVM: Simplify TLB_* macros")
    411740f5422a ("KVM: MIPS/MMU: Implement KVM_CAP_SYNC_MMU")
    748c0e312fce ("KVM: Make kvm_set_spte_hva() return int")
    8cffd1974851 ("MIPS: KVM: Convert code to kernel sized types")
    9fbfb06a4065 ("MIPS: KVM: Arrayify struct kvm_mips_tlb::tlb_lo*")
    ba049e93aef7 ("kvm: rename pfn_t to kvm_pfn_t")
    bdb7ed8608f8 ("MIPS: KVM: Convert headers to kernel sized types")
    ca64c2beecd4 ("MIPS: KVM: Abstract guest ASID mask")
    caa1faa7aba6 ("MIPS: KVM: Trivial whitespace and style fixes")


NOTE: The patch will not be queued to stable trees until it is upstream.

How should we proceed with this patch?

-- 
Thanks
Sasha