Merge branch 'for-5.16-vsprintf-pgp' into for-linus

1 files changed, 11 insertions, 10 deletions

diff --git a/arch/powerpc/perf/core-book3s.c b/arch/powerpc/perf/core-book3s.c
index bb0ee716de91..73e62e9b179b 100644
--- a/arch/powerpc/perf/core-book3s.c
+++ b/arch/powerpc/perf/core-book3s.c
@@ -340,6 +340,13 @@ static inline void perf_read_regs(struct pt_regs *regs)
 	 * If the PMU doesn't update the SIAR for non marked events use
 	 * pt_regs.
 	 *
+	 * If regs is a kernel interrupt, always use SIAR. Some PMUs have an
+	 * issue with regs_sipr not being in synch with SIAR in interrupt entry
+	 * and return sequences, which can result in regs_sipr being true for
+	 * kernel interrupts and SIAR, which has the effect of causing samples
+	 * to pile up at mtmsrd MSR[EE] 0->1 or pending irq replay around
+	 * interrupt entry/exit.
+	 *
 	 * If the PMU has HV/PR flags then check to see if they
 	 * place the exception in userspace. If so, use pt_regs. In
 	 * continuous sampling mode the SIAR and the PMU exception are
@@ -356,6 +363,8 @@ static inline void perf_read_regs(struct pt_regs *regs)
 		use_siar = 1;
 	else if ((ppmu->flags & PPMU_NO_CONT_SAMPLING))
 		use_siar = 0;
+	else if (!user_mode(regs))
+		use_siar = 1;
 	else if (!(ppmu->flags & PPMU_NO_SIPR) && regs_sipr(regs))
 		use_siar = 0;
 	else
@@ -2251,18 +2260,10 @@ unsigned long perf_misc_flags(struct pt_regs *regs)
  */
 unsigned long perf_instruction_pointer(struct pt_regs *regs)
 {
-	bool use_siar = regs_use_siar(regs);
 	unsigned long siar = mfspr(SPRN_SIAR);
 
-	if (ppmu && (ppmu->flags & PPMU_P10_DD1)) {
-		if (siar)
-			return siar;
-		else
-			return regs->nip;
-	} else if (use_siar && siar_valid(regs))
-		return mfspr(SPRN_SIAR) + perf_ip_adjust(regs);
-	else if (use_siar)
-		return 0;		// no valid instruction pointer
+	if (regs_use_siar(regs) && siar_valid(regs) && siar)
+		return siar + perf_ip_adjust(regs);
 	else
 		return regs->nip;
 }