Adding upstream version 6.6.15.upstream/6.6.15

Signed-off-by: Daniel Baumann <daniel.baumann@progress-linux.org>

1 files changed, 202 insertions, 0 deletions

diff --git a/arch/x86/kernel/perf_regs.c b/arch/x86/kernel/perf_regs.c
new file mode 100644
index 0000000000..624703af80
--- /dev/null
+++ b/arch/x86/kernel/perf_regs.c
@@ -0,0 +1,202 @@
+// SPDX-License-Identifier: GPL-2.0
+#include <linux/errno.h>
+#include <linux/kernel.h>
+#include <linux/sched.h>
+#include <linux/sched/task_stack.h>
+#include <linux/perf_event.h>
+#include <linux/bug.h>
+#include <linux/stddef.h>
+#include <asm/perf_regs.h>
+#include <asm/ptrace.h>
+
+#ifdef CONFIG_X86_32
+#define PERF_REG_X86_MAX PERF_REG_X86_32_MAX
+#else
+#define PERF_REG_X86_MAX PERF_REG_X86_64_MAX
+#endif
+
+#define PT_REGS_OFFSET(id, r) [id] = offsetof(struct pt_regs, r)
+
+static unsigned int pt_regs_offset[PERF_REG_X86_MAX] = {
+	PT_REGS_OFFSET(PERF_REG_X86_AX, ax),
+	PT_REGS_OFFSET(PERF_REG_X86_BX, bx),
+	PT_REGS_OFFSET(PERF_REG_X86_CX, cx),
+	PT_REGS_OFFSET(PERF_REG_X86_DX, dx),
+	PT_REGS_OFFSET(PERF_REG_X86_SI, si),
+	PT_REGS_OFFSET(PERF_REG_X86_DI, di),
+	PT_REGS_OFFSET(PERF_REG_X86_BP, bp),
+	PT_REGS_OFFSET(PERF_REG_X86_SP, sp),
+	PT_REGS_OFFSET(PERF_REG_X86_IP, ip),
+	PT_REGS_OFFSET(PERF_REG_X86_FLAGS, flags),
+	PT_REGS_OFFSET(PERF_REG_X86_CS, cs),
+	PT_REGS_OFFSET(PERF_REG_X86_SS, ss),
+#ifdef CONFIG_X86_32
+	PT_REGS_OFFSET(PERF_REG_X86_DS, ds),
+	PT_REGS_OFFSET(PERF_REG_X86_ES, es),
+	PT_REGS_OFFSET(PERF_REG_X86_FS, fs),
+	PT_REGS_OFFSET(PERF_REG_X86_GS, gs),
+#else
+	/*
+	 * The pt_regs struct does not store
+	 * ds, es, fs, gs in 64 bit mode.
+	 */
+	(unsigned int) -1,
+	(unsigned int) -1,
+	(unsigned int) -1,
+	(unsigned int) -1,
+#endif
+#ifdef CONFIG_X86_64
+	PT_REGS_OFFSET(PERF_REG_X86_R8, r8),
+	PT_REGS_OFFSET(PERF_REG_X86_R9, r9),
+	PT_REGS_OFFSET(PERF_REG_X86_R10, r10),
+	PT_REGS_OFFSET(PERF_REG_X86_R11, r11),
+	PT_REGS_OFFSET(PERF_REG_X86_R12, r12),
+	PT_REGS_OFFSET(PERF_REG_X86_R13, r13),
+	PT_REGS_OFFSET(PERF_REG_X86_R14, r14),
+	PT_REGS_OFFSET(PERF_REG_X86_R15, r15),
+#endif
+};
+
+u64 perf_reg_value(struct pt_regs *regs, int idx)
+{
+	struct x86_perf_regs *perf_regs;
+
+	if (idx >= PERF_REG_X86_XMM0 && idx < PERF_REG_X86_XMM_MAX) {
+		perf_regs = container_of(regs, struct x86_perf_regs, regs);
+		if (!perf_regs->xmm_regs)
+			return 0;
+		return perf_regs->xmm_regs[idx - PERF_REG_X86_XMM0];
+	}
+
+	if (WARN_ON_ONCE(idx >= ARRAY_SIZE(pt_regs_offset)))
+		return 0;
+
+	return regs_get_register(regs, pt_regs_offset[idx]);
+}
+
+#define PERF_REG_X86_RESERVED	(((1ULL << PERF_REG_X86_XMM0) - 1) & \
+				 ~((1ULL << PERF_REG_X86_MAX) - 1))
+
+#ifdef CONFIG_X86_32
+#define REG_NOSUPPORT ((1ULL << PERF_REG_X86_R8) | \
+		       (1ULL << PERF_REG_X86_R9) | \
+		       (1ULL << PERF_REG_X86_R10) | \
+		       (1ULL << PERF_REG_X86_R11) | \
+		       (1ULL << PERF_REG_X86_R12) | \
+		       (1ULL << PERF_REG_X86_R13) | \
+		       (1ULL << PERF_REG_X86_R14) | \
+		       (1ULL << PERF_REG_X86_R15))
+
+int perf_reg_validate(u64 mask)
+{
+	if (!mask || (mask & (REG_NOSUPPORT | PERF_REG_X86_RESERVED)))
+		return -EINVAL;
+
+	return 0;
+}
+
+u64 perf_reg_abi(struct task_struct *task)
+{
+	return PERF_SAMPLE_REGS_ABI_32;
+}
+
+void perf_get_regs_user(struct perf_regs *regs_user,
+			struct pt_regs *regs)
+{
+	regs_user->regs = task_pt_regs(current);
+	regs_user->abi = perf_reg_abi(current);
+}
+#else /* CONFIG_X86_64 */
+#define REG_NOSUPPORT ((1ULL << PERF_REG_X86_DS) | \
+		       (1ULL << PERF_REG_X86_ES) | \
+		       (1ULL << PERF_REG_X86_FS) | \
+		       (1ULL << PERF_REG_X86_GS))
+
+int perf_reg_validate(u64 mask)
+{
+	if (!mask || (mask & (REG_NOSUPPORT | PERF_REG_X86_RESERVED)))
+		return -EINVAL;
+
+	return 0;
+}
+
+u64 perf_reg_abi(struct task_struct *task)
+{
+	if (!user_64bit_mode(task_pt_regs(task)))
+		return PERF_SAMPLE_REGS_ABI_32;
+	else
+		return PERF_SAMPLE_REGS_ABI_64;
+}
+
+static DEFINE_PER_CPU(struct pt_regs, nmi_user_regs);
+
+void perf_get_regs_user(struct perf_regs *regs_user,
+			struct pt_regs *regs)
+{
+	struct pt_regs *regs_user_copy = this_cpu_ptr(&nmi_user_regs);
+	struct pt_regs *user_regs = task_pt_regs(current);
+
+	if (!in_nmi()) {
+		regs_user->regs = user_regs;
+		regs_user->abi = perf_reg_abi(current);
+		return;
+	}
+
+	/*
+	 * If we're in an NMI that interrupted task_pt_regs setup, then
+	 * we can't sample user regs at all.  This check isn't really
+	 * sufficient, though, as we could be in an NMI inside an interrupt
+	 * that happened during task_pt_regs setup.
+	 */
+	if (regs->sp > (unsigned long)&user_regs->r11 &&
+	    regs->sp <= (unsigned long)(user_regs + 1)) {
+		regs_user->abi = PERF_SAMPLE_REGS_ABI_NONE;
+		regs_user->regs = NULL;
+		return;
+	}
+
+	/*
+	 * These registers are always saved on 64-bit syscall entry.
+	 * On 32-bit entry points, they are saved too except r8..r11.
+	 */
+	regs_user_copy->ip = user_regs->ip;
+	regs_user_copy->ax = user_regs->ax;
+	regs_user_copy->cx = user_regs->cx;
+	regs_user_copy->dx = user_regs->dx;
+	regs_user_copy->si = user_regs->si;
+	regs_user_copy->di = user_regs->di;
+	regs_user_copy->r8 = user_regs->r8;
+	regs_user_copy->r9 = user_regs->r9;
+	regs_user_copy->r10 = user_regs->r10;
+	regs_user_copy->r11 = user_regs->r11;
+	regs_user_copy->orig_ax = user_regs->orig_ax;
+	regs_user_copy->flags = user_regs->flags;
+	regs_user_copy->sp = user_regs->sp;
+	regs_user_copy->cs = user_regs->cs;
+	regs_user_copy->ss = user_regs->ss;
+	/*
+	 * Store user space frame-pointer value on sample
+	 * to facilitate stack unwinding for cases when
+	 * user space executable code has such support
+	 * enabled at compile time:
+	 */
+	regs_user_copy->bp = user_regs->bp;
+
+	regs_user_copy->bx = -1;
+	regs_user_copy->r12 = -1;
+	regs_user_copy->r13 = -1;
+	regs_user_copy->r14 = -1;
+	regs_user_copy->r15 = -1;
+	/*
+	 * For this to be at all useful, we need a reasonable guess for
+	 * the ABI.  Be careful: we're in NMI context, and we're
+	 * considering current to be the current task, so we should
+	 * be careful not to look at any other percpu variables that might
+	 * change during context switches.
+	 */
+	regs_user->abi = user_64bit_mode(user_regs) ?
+		PERF_SAMPLE_REGS_ABI_64 : PERF_SAMPLE_REGS_ABI_32;
+
+	regs_user->regs = regs_user_copy;
+}
+#endif /* CONFIG_X86_32 */