diff options
author | Fenghua Yu <fenghua.yu@intel.com> | 2020-05-12 07:54:36 -0700 |
---|---|---|
committer | Borislav Petkov <bp@suse.de> | 2020-05-12 20:34:38 +0200 |
commit | 8ab22804efefea9ecf3c68aa00f1fa69c70fcfad (patch) | |
tree | 9a8dc8b23aab7ff9658b0c55a4e4d70ee00f07ae /arch/x86/kernel/fpu | |
parent | 5274e6c172c47241534e970df26a522497086624 (diff) |
x86/fpu/xstate: Define new macros for supervisor and user xstates
XCNTXT_MASK is 'all supported xfeatures' before introducing supervisor
xstates. Rename it to XFEATURE_MASK_USER_SUPPORTED to make clear that
these are user xstates.
Replace XFEATURE_MASK_SUPERVISOR with the following:
- XFEATURE_MASK_SUPERVISOR_SUPPORTED: Currently nothing. ENQCMD and
Control-flow Enforcement Technology (CET) will be introduced in separate
series.
- XFEATURE_MASK_SUPERVISOR_UNSUPPORTED: Currently only Processor Trace.
- XFEATURE_MASK_SUPERVISOR_ALL: the combination of above.
Co-developed-by: Yu-cheng Yu <yu-cheng.yu@intel.com>
Signed-off-by: Fenghua Yu <fenghua.yu@intel.com>
Signed-off-by: Yu-cheng Yu <yu-cheng.yu@intel.com>
Signed-off-by: Borislav Petkov <bp@suse.de>
Reviewed-by: Dave Hansen <dave.hansen@linux.intel.com>
Reviewed-by: Tony Luck <tony.luck@intel.com>
Link: https://lkml.kernel.org/r/20200512145444.15483-3-yu-cheng.yu@intel.com
Diffstat (limited to 'arch/x86/kernel/fpu')
-rw-r--r-- | arch/x86/kernel/fpu/init.c | 3 | ||||
-rw-r--r-- | arch/x86/kernel/fpu/xstate.c | 26 |
2 files changed, 15 insertions, 14 deletions
diff --git a/arch/x86/kernel/fpu/init.c b/arch/x86/kernel/fpu/init.c index 6ce7e0a23268..61ddc3a5e5c2 100644 --- a/arch/x86/kernel/fpu/init.c +++ b/arch/x86/kernel/fpu/init.c @@ -224,7 +224,8 @@ static void __init fpu__init_system_xstate_size_legacy(void) */ u64 __init fpu__get_supported_xfeatures_mask(void) { - return XCNTXT_MASK; + return XFEATURE_MASK_USER_SUPPORTED | + XFEATURE_MASK_SUPERVISOR_SUPPORTED; } /* Legacy code to initialize eager fpu mode. */ diff --git a/arch/x86/kernel/fpu/xstate.c b/arch/x86/kernel/fpu/xstate.c index 8ed64397c78b..9997df717339 100644 --- a/arch/x86/kernel/fpu/xstate.c +++ b/arch/x86/kernel/fpu/xstate.c @@ -208,14 +208,13 @@ void fpu__init_cpu_xstate(void) if (!boot_cpu_has(X86_FEATURE_XSAVE) || !xfeatures_mask) return; /* - * Make it clear that XSAVES supervisor states are not yet - * implemented should anyone expect it to work by changing - * bits in XFEATURE_MASK_* macros and XCR0. + * Unsupported supervisor xstates should not be found in + * the xfeatures mask. */ - WARN_ONCE((xfeatures_mask & XFEATURE_MASK_SUPERVISOR), - "x86/fpu: XSAVES supervisor states are not yet implemented.\n"); + WARN_ONCE((xfeatures_mask & XFEATURE_MASK_SUPERVISOR_UNSUPPORTED), + "x86/fpu: Found unsupported supervisor xstates.\n"); - xfeatures_mask &= ~XFEATURE_MASK_SUPERVISOR; + xfeatures_mask &= ~XFEATURE_MASK_SUPERVISOR_UNSUPPORTED; cr4_set_bits(X86_CR4_OSXSAVE); xsetbv(XCR_XFEATURE_ENABLED_MASK, xfeatures_mask); @@ -438,7 +437,7 @@ static int xfeature_uncompacted_offset(int xfeature_nr) * format. Checking a supervisor state's uncompacted offset is * an error. */ - if (XFEATURE_MASK_SUPERVISOR & BIT_ULL(xfeature_nr)) { + if (XFEATURE_MASK_SUPERVISOR_ALL & BIT_ULL(xfeature_nr)) { WARN_ONCE(1, "No fixed offset for xstate %d\n", xfeature_nr); return -1; } @@ -475,7 +474,7 @@ int using_compacted_format(void) int validate_user_xstate_header(const struct xstate_header *hdr) { /* No unknown or supervisor features may be set */ - if (hdr->xfeatures & (~xfeatures_mask | XFEATURE_MASK_SUPERVISOR)) + if (hdr->xfeatures & ~(xfeatures_mask & XFEATURE_MASK_USER_SUPPORTED)) return -EINVAL; /* Userspace must use the uncompacted format */ @@ -768,7 +767,8 @@ void __init fpu__init_system_xstate(void) * Update info used for ptrace frames; use standard-format size and no * supervisor xstates: */ - update_regset_xstate_info(fpu_user_xstate_size, xfeatures_mask & ~XFEATURE_MASK_SUPERVISOR); + update_regset_xstate_info(fpu_user_xstate_size, + xfeatures_mask & XFEATURE_MASK_USER_SUPPORTED); fpu__init_prepare_fx_sw_frame(); setup_init_fpu_buf(); @@ -996,7 +996,7 @@ int copy_xstate_to_kernel(void *kbuf, struct xregs_state *xsave, unsigned int of */ memset(&header, 0, sizeof(header)); header.xfeatures = xsave->header.xfeatures; - header.xfeatures &= ~XFEATURE_MASK_SUPERVISOR; + header.xfeatures &= XFEATURE_MASK_USER_SUPPORTED; /* * Copy xregs_state->header: @@ -1080,7 +1080,7 @@ int copy_xstate_to_user(void __user *ubuf, struct xregs_state *xsave, unsigned i */ memset(&header, 0, sizeof(header)); header.xfeatures = xsave->header.xfeatures; - header.xfeatures &= ~XFEATURE_MASK_SUPERVISOR; + header.xfeatures &= XFEATURE_MASK_USER_SUPPORTED; /* * Copy xregs_state->header: @@ -1173,7 +1173,7 @@ int copy_kernel_to_xstate(struct xregs_state *xsave, const void *kbuf) * The state that came in from userspace was user-state only. * Mask all the user states out of 'xfeatures': */ - xsave->header.xfeatures &= XFEATURE_MASK_SUPERVISOR; + xsave->header.xfeatures &= XFEATURE_MASK_SUPERVISOR_ALL; /* * Add back in the features that came in from userspace: @@ -1229,7 +1229,7 @@ int copy_user_to_xstate(struct xregs_state *xsave, const void __user *ubuf) * The state that came in from userspace was user-state only. * Mask all the user states out of 'xfeatures': */ - xsave->header.xfeatures &= XFEATURE_MASK_SUPERVISOR; + xsave->header.xfeatures &= XFEATURE_MASK_SUPERVISOR_ALL; /* * Add back in the features that came in from userspace: |