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authorMaxime Ripard <maxime@cerno.tech>2020-08-18 14:14:25 +0200
committerMaxime Ripard <maxime@cerno.tech>2020-08-18 14:14:25 +0200
commitd85ddd1318e66c0c2665dbfcbc21a8b66c9152aa (patch)
treee49e401abd2468b398d4bc84c7e05c2c2c3b0966 /arch/x86/include/asm/fpu
parentMAINTAINERS: Change maintainer for hisilicon DRM driver (diff)
parentLinux 5.9-rc1 (diff)
downloadlinux-dev-d85ddd1318e66c0c2665dbfcbc21a8b66c9152aa.tar.xz
linux-dev-d85ddd1318e66c0c2665dbfcbc21a8b66c9152aa.zip
Merge v5.9-rc1 into drm-misc-next
Sam needs 5.9-rc1 to have dev_err_probe in to merge some patches. Signed-off-by: Maxime Ripard <maxime@cerno.tech>
Diffstat (limited to 'arch/x86/include/asm/fpu')
-rw-r--r--arch/x86/include/asm/fpu/internal.h48
-rw-r--r--arch/x86/include/asm/fpu/regset.h4
-rw-r--r--arch/x86/include/asm/fpu/types.h27
-rw-r--r--arch/x86/include/asm/fpu/xstate.h40
4 files changed, 74 insertions, 45 deletions
diff --git a/arch/x86/include/asm/fpu/internal.h b/arch/x86/include/asm/fpu/internal.h
index 845e7481ab77..0a460f2a3f90 100644
--- a/arch/x86/include/asm/fpu/internal.h
+++ b/arch/x86/include/asm/fpu/internal.h
@@ -34,7 +34,6 @@ extern int fpu__copy(struct task_struct *dst, struct task_struct *src);
extern void fpu__clear_user_states(struct fpu *fpu);
extern void fpu__clear_all(struct fpu *fpu);
extern int fpu__exception_code(struct fpu *fpu, int trap_nr);
-extern int dump_fpu(struct pt_regs *ptregs, struct user_i387_struct *fpstate);
/*
* Boot time FPU initialization functions:
@@ -274,7 +273,7 @@ static inline void copy_fxregs_to_kernel(struct fpu *fpu)
*/
static inline void copy_xregs_to_kernel_booting(struct xregs_state *xstate)
{
- u64 mask = -1;
+ u64 mask = xfeatures_mask_all;
u32 lmask = mask;
u32 hmask = mask >> 32;
int err;
@@ -320,7 +319,7 @@ static inline void copy_kernel_to_xregs_booting(struct xregs_state *xstate)
*/
static inline void copy_xregs_to_kernel(struct xregs_state *xstate)
{
- u64 mask = -1;
+ u64 mask = xfeatures_mask_all;
u32 lmask = mask;
u32 hmask = mask >> 32;
int err;
@@ -356,6 +355,9 @@ static inline void copy_kernel_to_xregs(struct xregs_state *xstate, u64 mask)
*/
static inline int copy_xregs_to_user(struct xregs_state __user *buf)
{
+ u64 mask = xfeatures_mask_user();
+ u32 lmask = mask;
+ u32 hmask = mask >> 32;
int err;
/*
@@ -367,7 +369,7 @@ static inline int copy_xregs_to_user(struct xregs_state __user *buf)
return -EFAULT;
stac();
- XSTATE_OP(XSAVE, buf, -1, -1, err);
+ XSTATE_OP(XSAVE, buf, lmask, hmask, err);
clac();
return err;
@@ -408,43 +410,7 @@ static inline int copy_kernel_to_xregs_err(struct xregs_state *xstate, u64 mask)
return err;
}
-/*
- * These must be called with preempt disabled. Returns
- * 'true' if the FPU state is still intact and we can
- * keep registers active.
- *
- * The legacy FNSAVE instruction cleared all FPU state
- * unconditionally, so registers are essentially destroyed.
- * Modern FPU state can be kept in registers, if there are
- * no pending FP exceptions.
- */
-static inline int copy_fpregs_to_fpstate(struct fpu *fpu)
-{
- if (likely(use_xsave())) {
- copy_xregs_to_kernel(&fpu->state.xsave);
-
- /*
- * AVX512 state is tracked here because its use is
- * known to slow the max clock speed of the core.
- */
- if (fpu->state.xsave.header.xfeatures & XFEATURE_MASK_AVX512)
- fpu->avx512_timestamp = jiffies;
- return 1;
- }
-
- if (likely(use_fxsr())) {
- copy_fxregs_to_kernel(fpu);
- return 1;
- }
-
- /*
- * Legacy FPU register saving, FNSAVE always clears FPU registers,
- * so we have to mark them inactive:
- */
- asm volatile("fnsave %[fp]; fwait" : [fp] "=m" (fpu->state.fsave));
-
- return 0;
-}
+extern int copy_fpregs_to_fpstate(struct fpu *fpu);
static inline void __copy_kernel_to_fpregs(union fpregs_state *fpstate, u64 mask)
{
diff --git a/arch/x86/include/asm/fpu/regset.h b/arch/x86/include/asm/fpu/regset.h
index d5bdffb9d27f..4f928d6a367b 100644
--- a/arch/x86/include/asm/fpu/regset.h
+++ b/arch/x86/include/asm/fpu/regset.h
@@ -8,8 +8,8 @@
#include <linux/regset.h>
extern user_regset_active_fn regset_fpregs_active, regset_xregset_fpregs_active;
-extern user_regset_get_fn fpregs_get, xfpregs_get, fpregs_soft_get,
- xstateregs_get;
+extern user_regset_get2_fn fpregs_get, xfpregs_get, fpregs_soft_get,
+ xstateregs_get;
extern user_regset_set_fn fpregs_set, xfpregs_set, fpregs_soft_set,
xstateregs_set;
diff --git a/arch/x86/include/asm/fpu/types.h b/arch/x86/include/asm/fpu/types.h
index f098f6cab94b..c87364ea6446 100644
--- a/arch/x86/include/asm/fpu/types.h
+++ b/arch/x86/include/asm/fpu/types.h
@@ -114,6 +114,12 @@ enum xfeature {
XFEATURE_Hi16_ZMM,
XFEATURE_PT_UNIMPLEMENTED_SO_FAR,
XFEATURE_PKRU,
+ XFEATURE_RSRVD_COMP_10,
+ XFEATURE_RSRVD_COMP_11,
+ XFEATURE_RSRVD_COMP_12,
+ XFEATURE_RSRVD_COMP_13,
+ XFEATURE_RSRVD_COMP_14,
+ XFEATURE_LBR,
XFEATURE_MAX,
};
@@ -128,6 +134,7 @@ enum xfeature {
#define XFEATURE_MASK_Hi16_ZMM (1 << XFEATURE_Hi16_ZMM)
#define XFEATURE_MASK_PT (1 << XFEATURE_PT_UNIMPLEMENTED_SO_FAR)
#define XFEATURE_MASK_PKRU (1 << XFEATURE_PKRU)
+#define XFEATURE_MASK_LBR (1 << XFEATURE_LBR)
#define XFEATURE_MASK_FPSSE (XFEATURE_MASK_FP | XFEATURE_MASK_SSE)
#define XFEATURE_MASK_AVX512 (XFEATURE_MASK_OPMASK \
@@ -229,6 +236,26 @@ struct pkru_state {
u32 pad;
} __packed;
+/*
+ * State component 15: Architectural LBR configuration state.
+ * The size of Arch LBR state depends on the number of LBRs (lbr_depth).
+ */
+
+struct lbr_entry {
+ u64 from;
+ u64 to;
+ u64 info;
+};
+
+struct arch_lbr_state {
+ u64 lbr_ctl;
+ u64 lbr_depth;
+ u64 ler_from;
+ u64 ler_to;
+ u64 ler_info;
+ struct lbr_entry entries[];
+} __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 422d8369012a..14ab815132d4 100644
--- a/arch/x86/include/asm/fpu/xstate.h
+++ b/arch/x86/include/asm/fpu/xstate.h
@@ -21,6 +21,8 @@
#define XSAVE_YMM_SIZE 256
#define XSAVE_YMM_OFFSET (XSAVE_HDR_SIZE + XSAVE_HDR_OFFSET)
+#define XSAVE_ALIGNMENT 64
+
/* All currently supported user features */
#define XFEATURE_MASK_USER_SUPPORTED (XFEATURE_MASK_FP | \
XFEATURE_MASK_SSE | \
@@ -36,6 +38,27 @@
#define XFEATURE_MASK_SUPERVISOR_SUPPORTED (0)
/*
+ * A supervisor state component may not always contain valuable information,
+ * and its size may be huge. Saving/restoring such supervisor state components
+ * at each context switch can cause high CPU and space overhead, which should
+ * be avoided. Such supervisor state components should only be saved/restored
+ * on demand. The on-demand dynamic supervisor features are set in this mask.
+ *
+ * Unlike the existing supported supervisor features, a dynamic supervisor
+ * feature does not allocate a buffer in task->fpu, and the corresponding
+ * supervisor state component cannot be saved/restored at each context switch.
+ *
+ * To support a dynamic supervisor feature, a developer should follow the
+ * dos and don'ts as below:
+ * - Do dynamically allocate a buffer for the supervisor state component.
+ * - Do manually invoke the XSAVES/XRSTORS instruction to save/restore the
+ * state component to/from the buffer.
+ * - Don't set the bit corresponding to the dynamic supervisor feature in
+ * IA32_XSS at run time, since it has been set at boot time.
+ */
+#define XFEATURE_MASK_DYNAMIC (XFEATURE_MASK_LBR)
+
+/*
* Unsupported supervisor features. When a supervisor feature in this mask is
* supported in the future, move it to the supported supervisor feature mask.
*/
@@ -43,6 +66,7 @@
/* All supervisor states including supported and unsupported states. */
#define XFEATURE_MASK_SUPERVISOR_ALL (XFEATURE_MASK_SUPERVISOR_SUPPORTED | \
+ XFEATURE_MASK_DYNAMIC | \
XFEATURE_MASK_SUPERVISOR_UNSUPPORTED)
#ifdef CONFIG_X86_64
@@ -63,6 +87,14 @@ static inline u64 xfeatures_mask_user(void)
return xfeatures_mask_all & XFEATURE_MASK_USER_SUPPORTED;
}
+static inline u64 xfeatures_mask_dynamic(void)
+{
+ if (!boot_cpu_has(X86_FEATURE_ARCH_LBR))
+ return XFEATURE_MASK_DYNAMIC & ~XFEATURE_MASK_LBR;
+
+ return XFEATURE_MASK_DYNAMIC;
+}
+
extern u64 xstate_fx_sw_bytes[USER_XSTATE_FX_SW_WORDS];
extern void __init update_regset_xstate_info(unsigned int size,
@@ -71,11 +103,15 @@ extern void __init update_regset_xstate_info(unsigned int size,
void *get_xsave_addr(struct xregs_state *xsave, int xfeature_nr);
const void *get_xsave_field_ptr(int xfeature_nr);
int using_compacted_format(void);
-int copy_xstate_to_kernel(void *kbuf, struct xregs_state *xsave, unsigned int offset, unsigned int size);
-int copy_xstate_to_user(void __user *ubuf, struct xregs_state *xsave, unsigned int offset, unsigned int size);
+int xfeature_size(int xfeature_nr);
+struct membuf;
+void copy_xstate_to_kernel(struct membuf to, struct xregs_state *xsave);
int copy_kernel_to_xstate(struct xregs_state *xsave, const void *kbuf);
int copy_user_to_xstate(struct xregs_state *xsave, const void __user *ubuf);
void copy_supervisor_to_kernel(struct xregs_state *xsave);
+void copy_dynamic_supervisor_to_kernel(struct xregs_state *xstate, u64 mask);
+void copy_kernel_to_dynamic_supervisor(struct xregs_state *xstate, u64 mask);
+
/* Validate an xstate header supplied by userspace (ptrace or sigreturn) */
int validate_user_xstate_header(const struct xstate_header *hdr);