From c8df40098451ba18a43f22b563c9129182353158 Mon Sep 17 00:00:00 2001 From: Dave Hansen Date: Fri, 12 Feb 2016 13:02:04 -0800 Subject: [PATCH] x86/fpu, x86/mm/pkeys: Add PKRU xsave fields and data structures The protection keys register (PKRU) is saved and restored using xsave. Define the data structure that we will use to access it inside the xsave buffer. Note that we also have to widen the printk of the xsave feature masks since this is feature 0x200 and we only did two characters before. Signed-off-by: Dave Hansen Reviewed-by: Thomas Gleixner Cc: Andrew Morton Cc: Andy Lutomirski Cc: Borislav Petkov Cc: Brian Gerst Cc: Dave Hansen Cc: Denys Vlasenko Cc: H. Peter Anvin Cc: Linus Torvalds Cc: Peter Zijlstra Cc: Rik van Riel Cc: linux-mm@kvack.org Link: http://lkml.kernel.org/r/20160212210204.56DF8F7B@viggo.jf.intel.com Signed-off-by: Ingo Molnar --- arch/x86/include/asm/fpu/types.h | 11 +++++++++++ arch/x86/include/asm/fpu/xstate.h | 3 ++- arch/x86/kernel/fpu/xstate.c | 7 ++++++- 3 files changed, 19 insertions(+), 2 deletions(-) diff --git a/arch/x86/include/asm/fpu/types.h b/arch/x86/include/asm/fpu/types.h index aad3181c9b7b..36b90bbfc69f 100644 --- a/arch/x86/include/asm/fpu/types.h +++ b/arch/x86/include/asm/fpu/types.h @@ -109,6 +109,7 @@ enum xfeature { XFEATURE_ZMM_Hi256, XFEATURE_Hi16_ZMM, XFEATURE_PT_UNIMPLEMENTED_SO_FAR, + XFEATURE_PKRU, XFEATURE_MAX, }; @@ -121,6 +122,7 @@ enum xfeature { #define XFEATURE_MASK_OPMASK (1 << XFEATURE_OPMASK) #define XFEATURE_MASK_ZMM_Hi256 (1 << XFEATURE_ZMM_Hi256) #define XFEATURE_MASK_Hi16_ZMM (1 << XFEATURE_Hi16_ZMM) +#define XFEATURE_MASK_PKRU (1 << XFEATURE_PKRU) #define XFEATURE_MASK_FPSSE (XFEATURE_MASK_FP | XFEATURE_MASK_SSE) #define XFEATURE_MASK_AVX512 (XFEATURE_MASK_OPMASK \ @@ -213,6 +215,15 @@ struct avx_512_hi16_state { struct reg_512_bit hi16_zmm[16]; } __packed; +/* + * State component 9: 32-bit PKRU register. The state is + * 8 bytes long but only 4 bytes is used currently. + */ +struct pkru_state { + u32 pkru; + u32 pad; +} __packed; + struct xstate_header { u64 xfeatures; u64 xcomp_bv; diff --git a/arch/x86/include/asm/fpu/xstate.h b/arch/x86/include/asm/fpu/xstate.h index af30fdeb140d..9994d4229002 100644 --- a/arch/x86/include/asm/fpu/xstate.h +++ b/arch/x86/include/asm/fpu/xstate.h @@ -28,7 +28,8 @@ XFEATURE_MASK_YMM | \ XFEATURE_MASK_OPMASK | \ XFEATURE_MASK_ZMM_Hi256 | \ - XFEATURE_MASK_Hi16_ZMM) + XFEATURE_MASK_Hi16_ZMM | \ + XFEATURE_MASK_PKRU) /* All currently supported features */ #define XCNTXT_MASK (XFEATURE_MASK_LAZY | XFEATURE_MASK_EAGER) diff --git a/arch/x86/kernel/fpu/xstate.c b/arch/x86/kernel/fpu/xstate.c index c2e2349dbcfe..a63ca80fa723 100644 --- a/arch/x86/kernel/fpu/xstate.c +++ b/arch/x86/kernel/fpu/xstate.c @@ -29,6 +29,8 @@ static const char *xfeature_names[] = "AVX-512 Hi256" , "AVX-512 ZMM_Hi256" , "Processor Trace (unused)" , + "Protection Keys User registers", + "unknown xstate feature" , }; /* @@ -58,6 +60,7 @@ void fpu__xstate_clear_all_cpu_caps(void) setup_clear_cpu_cap(X86_FEATURE_AVX512CD); setup_clear_cpu_cap(X86_FEATURE_MPX); setup_clear_cpu_cap(X86_FEATURE_XGETBV1); + setup_clear_cpu_cap(X86_FEATURE_PKU); } /* @@ -236,7 +239,7 @@ static void __init print_xstate_feature(u64 xstate_mask) const char *feature_name; if (cpu_has_xfeatures(xstate_mask, &feature_name)) - pr_info("x86/fpu: Supporting XSAVE feature 0x%02Lx: '%s'\n", xstate_mask, feature_name); + pr_info("x86/fpu: Supporting XSAVE feature 0x%03Lx: '%s'\n", xstate_mask, feature_name); } /* @@ -252,6 +255,7 @@ static void __init print_xstate_features(void) print_xstate_feature(XFEATURE_MASK_OPMASK); print_xstate_feature(XFEATURE_MASK_ZMM_Hi256); print_xstate_feature(XFEATURE_MASK_Hi16_ZMM); + print_xstate_feature(XFEATURE_MASK_PKRU); } /* @@ -468,6 +472,7 @@ static void check_xstate_against_struct(int nr) XCHECK_SZ(sz, nr, XFEATURE_OPMASK, struct avx_512_opmask_state); XCHECK_SZ(sz, nr, XFEATURE_ZMM_Hi256, struct avx_512_zmm_uppers_state); XCHECK_SZ(sz, nr, XFEATURE_Hi16_ZMM, struct avx_512_hi16_state); + XCHECK_SZ(sz, nr, XFEATURE_PKRU, struct pkru_state); /* * Make *SURE* to add any feature numbers in below if -- 2.20.1