diff options
| author | Yanan Wang <wangyanan55@huawei.com> | 2020-12-02 04:10:34 +0800 |
|---|---|---|
| committer | Marc Zyngier <maz@kernel.org> | 2020-12-02 09:53:29 +0000 |
| commit | 7d894834a305568a0168c55d4729216f5f8cb4e6 (patch) | |
| tree | b08b0bdcf2f27ff3e775be9dbfb827645d81e416 /arch/arm64/include/asm/esr.h | |
| parent | 3a0b870e3448302ca2ba703bea1b79b61c3f33c6 (diff) | |
KVM: arm64: Add usage of stage 2 fault lookup level in user_mem_abort()
If we get a FSC_PERM fault, just using (logging_active && writable) to
determine calling kvm_pgtable_stage2_map(). There will be two more cases
we should consider.
(1) After logging_active is configged back to false from true. When we
get a FSC_PERM fault with write_fault and adjustment of hugepage is needed,
we should merge tables back to a block entry. This case is ignored by still
calling kvm_pgtable_stage2_relax_perms(), which will lead to an endless
loop and guest panic due to soft lockup.
(2) We use (FSC_PERM && logging_active && writable) to determine
collapsing a block entry into a table by calling kvm_pgtable_stage2_map().
But sometimes we may only need to relax permissions when trying to write
to a page other than a block.
In this condition,using kvm_pgtable_stage2_relax_perms() will be fine.
The ISS filed bit[1:0] in ESR_EL2 regesiter indicates the stage2 lookup
level at which a D-abort or I-abort occurred. By comparing granule of
the fault lookup level with vma_pagesize, we can strictly distinguish
conditions of calling kvm_pgtable_stage2_relax_perms() or
kvm_pgtable_stage2_map(), and the above two cases will be well considered.
Suggested-by: Keqian Zhu <zhukeqian1@huawei.com>
Signed-off-by: Yanan Wang <wangyanan55@huawei.com>
Signed-off-by: Marc Zyngier <maz@kernel.org>
Acked-by: Will Deacon <will@kernel.org>
Link: https://lore.kernel.org/r/20201201201034.116760-4-wangyanan55@huawei.com
Diffstat (limited to 'arch/arm64/include/asm/esr.h')
| -rw-r--r-- | arch/arm64/include/asm/esr.h | 1 |
1 files changed, 1 insertions, 0 deletions
diff --git a/arch/arm64/include/asm/esr.h b/arch/arm64/include/asm/esr.h index 22c81f1edda2..85a3e49f92f4 100644 --- a/arch/arm64/include/asm/esr.h +++ b/arch/arm64/include/asm/esr.h @@ -104,6 +104,7 @@ /* Shared ISS fault status code(IFSC/DFSC) for Data/Instruction aborts */ #define ESR_ELx_FSC (0x3F) #define ESR_ELx_FSC_TYPE (0x3C) +#define ESR_ELx_FSC_LEVEL (0x03) #define ESR_ELx_FSC_EXTABT (0x10) #define ESR_ELx_FSC_SERROR (0x11) #define ESR_ELx_FSC_ACCESS (0x08) |