linux-kernel.vger.kernel.org archive mirror
 help / color / mirror / Atom feed
* [PATCH] powerpc/32: Fix unpaired stwcx. on interrupt exit
@ 2025-08-27 14:19 Christophe Leroy
  0 siblings, 0 replies; only message in thread
From: Christophe Leroy @ 2025-08-27 14:19 UTC (permalink / raw)
  To: Michael Ellerman, Nicholas Piggin, Madhavan Srinivasan
  Cc: Christophe Leroy, linux-kernel, linuxppc-dev

Commit b64f87c16f3c ("[POWERPC] Avoid unpaired stwcx. on some
processors") erroneouly copied to powerpc/32 the logic from powerpc/64
based on feature CPU_FTR_STCX_CHECKS_ADDRESS which is always 0 on
powerpc/32.

Re-instate the logic implemented by commit b64f87c16f3c ("[POWERPC]
Avoid unpaired stwcx. on some processors")

Fixes: b96bae3ae2cb ("powerpc/32: Replace ASM exception exit by C exception exit from ppc64")
Signed-off-by: Christophe Leroy <christophe.leroy@csgroup.eu>
---
 arch/powerpc/kernel/entry_32.S | 10 ++++------
 1 file changed, 4 insertions(+), 6 deletions(-)

diff --git a/arch/powerpc/kernel/entry_32.S b/arch/powerpc/kernel/entry_32.S
index 762df811433c..c37480176a1c 100644
--- a/arch/powerpc/kernel/entry_32.S
+++ b/arch/powerpc/kernel/entry_32.S
@@ -260,10 +260,9 @@ interrupt_return:
 	mtspr	SPRN_SRR1,r12
 
 BEGIN_FTR_SECTION
+	lwarx   r0,0,r1
+END_FTR_SECTION_IFSET(CPU_FTR_NEED_PAIRED_STWCX)
 	stwcx.	r0,0,r1		/* to clear the reservation */
-FTR_SECTION_ELSE
-	lwarx	r0,0,r1
-ALT_FTR_SECTION_END_IFCLR(CPU_FTR_STCX_CHECKS_ADDRESS)
 
 	lwz	r3,_CCR(r1)
 	lwz	r4,_LINK(r1)
@@ -303,10 +302,9 @@ ALT_FTR_SECTION_END_IFCLR(CPU_FTR_STCX_CHECKS_ADDRESS)
 	mtspr	SPRN_SRR1,r12
 
 BEGIN_FTR_SECTION
+	lwarx   r0,0,r1
+END_FTR_SECTION_IFSET(CPU_FTR_NEED_PAIRED_STWCX)
 	stwcx.	r0,0,r1		/* to clear the reservation */
-FTR_SECTION_ELSE
-	lwarx	r0,0,r1
-ALT_FTR_SECTION_END_IFCLR(CPU_FTR_STCX_CHECKS_ADDRESS)
 
 	lwz	r3,_LINK(r1)
 	lwz	r4,_CTR(r1)
-- 
2.49.0


^ permalink raw reply related	[flat|nested] only message in thread

only message in thread, other threads:[~2025-08-27 14:50 UTC | newest]

Thread overview: (only message) (download: mbox.gz follow: Atom feed
-- links below jump to the message on this page --
2025-08-27 14:19 [PATCH] powerpc/32: Fix unpaired stwcx. on interrupt exit Christophe Leroy

This is a public inbox, see mirroring instructions
for how to clone and mirror all data and code used for this inbox;
as well as URLs for NNTP newsgroup(s).