1 files changed, 122 insertions, 19 deletions

diff --git a/arch/x86/kernel/fpu/xstate.c b/arch/x86/kernel/fpu/xstate.c
index 117e74c44e75..27417b685c1d 100644
--- a/arch/x86/kernel/fpu/xstate.c
+++ b/arch/x86/kernel/fpu/xstate.c
@@ -13,16 +13,20 @@
 #include <linux/seq_file.h>
 #include <linux/proc_fs.h>
 #include <linux/vmalloc.h>
+#include <linux/coredump.h>
 
 #include <asm/fpu/api.h>
 #include <asm/fpu/regset.h>
 #include <asm/fpu/signal.h>
 #include <asm/fpu/xcr.h>
 
+#include <asm/cpuid.h>
 #include <asm/tlbflush.h>
 #include <asm/prctl.h>
 #include <asm/elf.h>
 
+#include <uapi/asm/elf.h>
+
 #include "context.h"
 #include "internal.h"
 #include "legacy.h"
@@ -178,10 +182,11 @@ void fpu__init_cpu_xstate(void)
 	 * Must happen after CR4 setup and before xsetbv() to allow KVM
 	 * lazy passthrough.  Write independent of the dynamic state static
 	 * key as that does not work on the boot CPU. This also ensures
-	 * that any stale state is wiped out from XFD.
+	 * that any stale state is wiped out from XFD. Reset the per CPU
+	 * xfd cache too.
 	 */
 	if (cpu_feature_enabled(X86_FEATURE_XFD))
-		wrmsrl(MSR_IA32_XFD, init_fpstate.xfd);
+		xfd_set_state(init_fpstate.xfd);
 
 	/*
 	 * XCR_XFEATURE_ENABLED_MASK (aka. XCR0) sets user features
@@ -228,7 +233,7 @@ static void __init setup_xstate_cache(void)
 						       xmm_space);
 
 	for_each_extended_xfeature(i, fpu_kernel_cfg.max_features) {
-		cpuid_count(XSTATE_CPUID, i, &eax, &ebx, &ecx, &edx);
+		cpuid_count(CPUID_LEAF_XSTATE, i, &eax, &ebx, &ecx, &edx);
 
 		xstate_sizes[i] = eax;
 		xstate_flags[i] = ecx;
@@ -394,7 +399,7 @@ int xfeature_size(int xfeature_nr)
 	u32 eax, ebx, ecx, edx;
 
 	CHECK_XFEATURE(xfeature_nr);
-	cpuid_count(XSTATE_CPUID, xfeature_nr, &eax, &ebx, &ecx, &edx);
+	cpuid_count(CPUID_LEAF_XSTATE, xfeature_nr, &eax, &ebx, &ecx, &edx);
 	return eax;
 }
 
@@ -437,9 +442,9 @@ static void __init __xstate_dump_leaves(void)
 	 * just in case there are some goodies up there
 	 */
 	for (i = 0; i < XFEATURE_MAX + 10; i++) {
-		cpuid_count(XSTATE_CPUID, i, &eax, &ebx, &ecx, &edx);
+		cpuid_count(CPUID_LEAF_XSTATE, i, &eax, &ebx, &ecx, &edx);
 		pr_warn("CPUID[%02x, %02x]: eax=%08x ebx=%08x ecx=%08x edx=%08x\n",
-			XSTATE_CPUID, i, eax, ebx, ecx, edx);
+			CPUID_LEAF_XSTATE, i, eax, ebx, ecx, edx);
 	}
 }
 
@@ -480,7 +485,7 @@ static int __init check_xtile_data_against_struct(int size)
 	 * Check the maximum palette id:
 	 *   eax: the highest numbered palette subleaf.
 	 */
-	cpuid_count(TILE_CPUID, 0, &max_palid, &ebx, &ecx, &edx);
+	cpuid_count(CPUID_LEAF_TILE, 0, &max_palid, &ebx, &ecx, &edx);
 
 	/*
 	 * Cross-check each tile size and find the maximum number of
@@ -494,7 +499,7 @@ static int __init check_xtile_data_against_struct(int size)
 		 *   eax[31:16]:  bytes per title
 		 *   ebx[31:16]:  the max names (or max number of tiles)
 		 */
-		cpuid_count(TILE_CPUID, palid, &eax, &ebx, &edx, &edx);
+		cpuid_count(CPUID_LEAF_TILE, palid, &eax, &ebx, &edx, &edx);
 		tile_size = eax >> 16;
 		max = ebx >> 16;
 
@@ -629,7 +634,7 @@ static unsigned int __init get_compacted_size(void)
 	 * are no supervisor states, but XSAVEC still uses compacted
 	 * format.
 	 */
-	cpuid_count(XSTATE_CPUID, 1, &eax, &ebx, &ecx, &edx);
+	cpuid_count(CPUID_LEAF_XSTATE, 1, &eax, &ebx, &ecx, &edx);
 	return ebx;
 }
 
@@ -670,7 +675,7 @@ static unsigned int __init get_xsave_size_user(void)
 	 *    containing all the *user* state components
 	 *    corresponding to bits currently set in XCR0.
 	 */
-	cpuid_count(XSTATE_CPUID, 0, &eax, &ebx, &ecx, &edx);
+	cpuid_count(CPUID_LEAF_XSTATE, 0, &eax, &ebx, &ecx, &edx);
 	return ebx;
 }
 
@@ -759,21 +764,16 @@ void __init fpu__init_system_xstate(unsigned int legacy_size)
 		return;
 	}
 
-	if (boot_cpu_data.cpuid_level < XSTATE_CPUID) {
-		WARN_ON_FPU(1);
-		return;
-	}
-
 	/*
 	 * Find user xstates supported by the processor.
 	 */
-	cpuid_count(XSTATE_CPUID, 0, &eax, &ebx, &ecx, &edx);
+	cpuid_count(CPUID_LEAF_XSTATE, 0, &eax, &ebx, &ecx, &edx);
 	fpu_kernel_cfg.max_features = eax + ((u64)edx << 32);
 
 	/*
 	 * Find supervisor xstates supported by the processor.
 	 */
-	cpuid_count(XSTATE_CPUID, 1, &eax, &ebx, &ecx, &edx);
+	cpuid_count(CPUID_LEAF_XSTATE, 1, &eax, &ebx, &ecx, &edx);
 	fpu_kernel_cfg.max_features |= ecx + ((u64)edx << 32);
 
 	if ((fpu_kernel_cfg.max_features & XFEATURE_MASK_FPSSE) != XFEATURE_MASK_FPSSE) {
@@ -787,6 +787,9 @@ void __init fpu__init_system_xstate(unsigned int legacy_size)
 		goto out_disable;
 	}
 
+	fpu_kernel_cfg.independent_features = fpu_kernel_cfg.max_features &
+					      XFEATURE_MASK_INDEPENDENT;
+
 	/*
 	 * Clear XSAVE features that are disabled in the normal CPUID.
 	 */
@@ -990,6 +993,20 @@ void *get_xsave_addr(struct xregs_state *xsave, int xfeature_nr)
 
 	return __raw_xsave_addr(xsave, xfeature_nr);
 }
+EXPORT_SYMBOL_GPL(get_xsave_addr);
+
+/*
+ * Given an xstate feature nr, calculate where in the xsave buffer the state is.
+ * The xsave buffer should be in standard format, not compacted (e.g. user mode
+ * signal frames).
+ */
+void __user *get_xsave_addr_user(struct xregs_state __user *xsave, int xfeature_nr)
+{
+	if (WARN_ON_ONCE(!xfeature_enabled(xfeature_nr)))
+		return NULL;
+
+	return (void __user *)xsave + xstate_offsets[xfeature_nr];
+}
 
 #ifdef CONFIG_ARCH_HAS_PKEYS
 
@@ -1433,8 +1450,8 @@ static bool xstate_op_valid(struct fpstate *fpstate, u64 mask, bool rstor)
 		return rstor;
 
 	/*
-	 * XSAVE(S): clone(), fpu_swap_kvm_fpu()
-	 * XRSTORS(S): fpu_swap_kvm_fpu()
+	 * XSAVE(S): clone(), fpu_swap_kvm_fpstate()
+	 * XRSTORS(S): fpu_swap_kvm_fpstate()
 	 */
 
 	/*
@@ -1836,3 +1853,89 @@ int proc_pid_arch_status(struct seq_file *m, struct pid_namespace *ns,
 	return 0;
 }
 #endif /* CONFIG_PROC_PID_ARCH_STATUS */
+
+#ifdef CONFIG_COREDUMP
+static const char owner_name[] = "LINUX";
+
+/*
+ * Dump type, size, offset and flag values for every xfeature that is present.
+ */
+static int dump_xsave_layout_desc(struct coredump_params *cprm)
+{
+	int num_records = 0;
+	int i;
+
+	for_each_extended_xfeature(i, fpu_user_cfg.max_features) {
+		struct x86_xfeat_component xc = {
+			.type   = i,
+			.size   = xstate_sizes[i],
+			.offset = xstate_offsets[i],
+			/* reserved for future use */
+			.flags  = 0,
+		};
+
+		if (!dump_emit(cprm, &xc, sizeof(xc)))
+			return 0;
+
+		num_records++;
+	}
+	return num_records;
+}
+
+static u32 get_xsave_desc_size(void)
+{
+	u32 cnt = 0;
+	u32 i;
+
+	for_each_extended_xfeature(i, fpu_user_cfg.max_features)
+		cnt++;
+
+	return cnt * (sizeof(struct x86_xfeat_component));
+}
+
+int elf_coredump_extra_notes_write(struct coredump_params *cprm)
+{
+	int num_records = 0;
+	struct elf_note en;
+
+	if (!fpu_user_cfg.max_features)
+		return 0;
+
+	en.n_namesz = sizeof(owner_name);
+	en.n_descsz = get_xsave_desc_size();
+	en.n_type = NT_X86_XSAVE_LAYOUT;
+
+	if (!dump_emit(cprm, &en, sizeof(en)))
+		return 1;
+	if (!dump_emit(cprm, owner_name, en.n_namesz))
+		return 1;
+	if (!dump_align(cprm, 4))
+		return 1;
+
+	num_records = dump_xsave_layout_desc(cprm);
+	if (!num_records)
+		return 1;
+
+	/* Total size should be equal to the number of records */
+	if ((sizeof(struct x86_xfeat_component) * num_records) != en.n_descsz)
+		return 1;
+
+	return 0;
+}
+
+int elf_coredump_extra_notes_size(void)
+{
+	int size;
+
+	if (!fpu_user_cfg.max_features)
+		return 0;
+
+	/* .note header */
+	size  = sizeof(struct elf_note);
+	/*  Name plus alignment to 4 bytes */
+	size += roundup(sizeof(owner_name), 4);
+	size += get_xsave_desc_size();
+
+	return size;
+}
+#endif /* CONFIG_COREDUMP */