6.1-stable review patch. If anyone has any objections, please let me know.
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From: Christophe Leroy christophe.leroy@csgroup.eu
[ Upstream commit 10e1c77c3636d815db802ceef588522c2d2d947c ]
Commit b96bae3ae2cb ("powerpc/32: Replace ASM exception exit by C exception exit from ppc64") 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") which is based on CPU_FTR_NEED_PAIRED_STWCX feature.
Fixes: b96bae3ae2cb ("powerpc/32: Replace ASM exception exit by C exception exit from ppc64") Signed-off-by: Christophe Leroy christophe.leroy@csgroup.eu Signed-off-by: Madhavan Srinivasan maddy@linux.ibm.com Link: https://patch.msgid.link/6040b5dbcf5cdaa1cd919fcf0790f12974ea6e5a.1757666244... Signed-off-by: Sasha Levin sashal@kernel.org --- 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 d4fc546762db4..ca0f0abc49262 100644 --- a/arch/powerpc/kernel/entry_32.S +++ b/arch/powerpc/kernel/entry_32.S @@ -310,10 +310,9 @@ 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) @@ -356,10 +355,9 @@ 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)