Messages in this thread Patch in this message | | | Subject | [PATCH 05/12] x86, pkeys: new page fault error code bit: PF_PK | From | Dave Hansen <> | Date | Thu, 07 May 2015 10:41:34 -0700 |
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Note: "PK" is how the Intel SDM refers to this bit, so we also use that nomenclature.
This only defines the bit, it does not plumb it anywhere to be handled.
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b/arch/x86/mm/fault.c | 7 ++++++- 1 file changed, 6 insertions(+), 1 deletion(-)
diff -puN arch/x86/mm/fault.c~pkeys-4-pfec arch/x86/mm/fault.c --- a/arch/x86/mm/fault.c~pkeys-4-pfec 2015-05-07 10:31:42.568240681 -0700 +++ b/arch/x86/mm/fault.c 2015-05-07 10:31:42.571240816 -0700 @@ -31,6 +31,7 @@ * bit 2 == 0: kernel-mode access 1: user-mode access * bit 3 == 1: use of reserved bit detected * bit 4 == 1: fault was an instruction fetch + * bit 5 == 1: protection keys block access */ enum x86_pf_error_code { @@ -39,6 +40,7 @@ enum x86_pf_error_code { PF_USER = 1 << 2, PF_RSVD = 1 << 3, PF_INSTR = 1 << 4, + PF_PK = 1 << 5, }; /* @@ -912,7 +914,10 @@ static int spurious_fault_check(unsigned if ((error_code & PF_INSTR) && !pte_exec(*pte)) return 0; - + /* + * Note: We do not do lazy flushing on protection key + * changes, so no spurious fault will ever set PF_PK. + */ return 1; } _
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