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author | Zhenyu Ye <yezhenyu2@huawei.com> | 2021-06-23 10:05:22 +0300 |
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committer | Greg Kroah-Hartman <gregkh@linuxfoundation.org> | 2021-07-19 11:04:50 +0300 |
commit | dcb4b49e3ced01bb3e3ac69cb394accf5615cda1 (patch) | |
tree | e697f028ace175ce817fa851b3cd51816217a7a0 /arch | |
parent | 31d1d7db49785d74b388c55a5e33bad02061ef35 (diff) | |
download | linux-dcb4b49e3ced01bb3e3ac69cb394accf5615cda1.tar.xz |
arm64: tlb: fix the TTL value of tlb_get_level
commit 52218fcd61cb42bde0d301db4acb3ffdf3463cc7 upstream.
The TTL field indicates the level of page table walk holding the *leaf*
entry for the address being invalidated. But currently, the TTL field
may be set to an incorrent value in the following stack:
pte_free_tlb
__pte_free_tlb
tlb_remove_table
tlb_table_invalidate
tlb_flush_mmu_tlbonly
tlb_flush
In this case, we just want to flush a PTE page, but the tlb->cleared_pmds
is set and we get tlb_level = 2 in the tlb_get_level() function. This may
cause some unexpected problems.
This patch set the TTL field to 0 if tlb->freed_tables is set. The
tlb->freed_tables indicates page table pages are freed, not the leaf
entry.
Cc: <stable@vger.kernel.org> # 5.9.x
Fixes: c4ab2cbc1d87 ("arm64: tlb: Set the TTL field in flush_tlb_range")
Acked-by: Catalin Marinas <catalin.marinas@arm.com>
Reported-by: ZhuRui <zhurui3@huawei.com>
Signed-off-by: Zhenyu Ye <yezhenyu2@huawei.com>
Link: https://lore.kernel.org/r/b80ead47-1f88-3a00-18e1-cacc22f54cc4@huawei.com
Signed-off-by: Will Deacon <will@kernel.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Diffstat (limited to 'arch')
-rw-r--r-- | arch/arm64/include/asm/tlb.h | 4 |
1 files changed, 4 insertions, 0 deletions
diff --git a/arch/arm64/include/asm/tlb.h b/arch/arm64/include/asm/tlb.h index 61c97d3b58c7..c995d1f4594f 100644 --- a/arch/arm64/include/asm/tlb.h +++ b/arch/arm64/include/asm/tlb.h @@ -28,6 +28,10 @@ static void tlb_flush(struct mmu_gather *tlb); */ static inline int tlb_get_level(struct mmu_gather *tlb) { + /* The TTL field is only valid for the leaf entry. */ + if (tlb->freed_tables) + return 0; + if (tlb->cleared_ptes && !(tlb->cleared_pmds || tlb->cleared_puds || tlb->cleared_p4ds)) |