Commit-ID: b3ecd51559ae7a8f40b10443773b9cd0e6a50f5e Gitweb: http://git.kernel.org/tip/b3ecd51559ae7a8f40b10443773b9cd0e6a50f5e Author: Dave Hansen <[email protected]> AuthorDate: Fri, 12 Feb 2016 13:02:07 -0800 Committer: Ingo Molnar <[email protected]> CommitDate: Thu, 18 Feb 2016 09:31:50 +0100
x86/mm/pkeys: Add new 'PF_PK' page fault error code bit 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. Signed-off-by: Dave Hansen <[email protected]> Reviewed-by: Thomas Gleixner <[email protected]> Cc: Andrew Morton <[email protected]> Cc: Andy Lutomirski <[email protected]> Cc: Borislav Petkov <[email protected]> Cc: Brian Gerst <[email protected]> Cc: Dave Hansen <[email protected]> Cc: Denys Vlasenko <[email protected]> Cc: H. Peter Anvin <[email protected]> Cc: Linus Torvalds <[email protected]> Cc: Peter Zijlstra <[email protected]> Cc: Rik van Riel <[email protected]> Cc: [email protected] Link: http://lkml.kernel.org/r/[email protected] Signed-off-by: Ingo Molnar <[email protected]> --- arch/x86/mm/fault.c | 8 ++++++++ 1 file changed, 8 insertions(+) diff --git a/arch/x86/mm/fault.c b/arch/x86/mm/fault.c index eef44d9..9f72f9c 100644 --- a/arch/x86/mm/fault.c +++ b/arch/x86/mm/fault.c @@ -33,6 +33,7 @@ * 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 { @@ -41,6 +42,7 @@ enum x86_pf_error_code { PF_USER = 1 << 2, PF_RSVD = 1 << 3, PF_INSTR = 1 << 4, + PF_PK = 1 << 5, }; /* @@ -916,6 +918,12 @@ static int spurious_fault_check(unsigned long error_code, pte_t *pte) 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. + */ + if ((error_code & PF_PK)) + return 1; return 1; }
