[PATCH v2 35/43] powerpc/32: Save remaining registers in exception prolog
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STALE2050d
SUPERSEDED
From: Christophe Leroy <hidden>
Date: 2021-03-09 12:11:20
Also in:
lkml
Subsystem:
linux for powerpc (32-bit and 64-bit), the rest · Maintainers:
Madhavan Srinivasan, Linus Torvalds
Revision v2 of 3 in this series.
Revisions (3)
- v1 [diff vs current]
- v2 current
- v3 [diff vs current]
Save non volatile registers, XER, CTR, MSR and NIP in exception prolog. Also assign proper value to r2 and r3 there. For now, recalculate thread pointer in prepare_transfer_to_handler. It will disappear once KUAP is ported to C. And remove the comment which is now completely wrong. Signed-off-by: Christophe Leroy <redacted> --- arch/powerpc/kernel/entry_32.S | 25 +++---------------------- arch/powerpc/kernel/head_32.h | 12 ++++++++++++ 2 files changed, 15 insertions(+), 22 deletions(-)
diff --git a/arch/powerpc/kernel/entry_32.S b/arch/powerpc/kernel/entry_32.S
index 289f111a5ac7..8fe1c3fdfa6e 100644
--- a/arch/powerpc/kernel/entry_32.S
+++ b/arch/powerpc/kernel/entry_32.S@@ -48,29 +48,11 @@ */ .align 12 -/* - * This code finishes saving the registers to the exception frame - * and jumps to the appropriate handler for the exception, turning - * on address translation. - * Note that we rely on the caller having set cr0.eq iff the exception - * occurred in kernel mode (i.e. MSR:PR = 0). - */ .globl prepare_transfer_to_handler prepare_transfer_to_handler: - SAVE_NVGPRS(r11) - addi r3,r1,STACK_FRAME_OVERHEAD - stw r2,GPR2(r11) - stw r12,_NIP(r11) - stw r9,_MSR(r11) - andi. r2,r9,MSR_PR - mfctr r12 - mfspr r2,SPRN_XER - stw r12,_CTR(r11) - stw r2,_XER(r11) - mfspr r12,SPRN_SPRG_THREAD - tovirt(r12, r12) + andi. r0,r9,MSR_PR + addi r12, r2, THREAD beq 2f /* if from user, fix up THREAD.regs */ - addi r2, r12, -THREAD stw r3,PT_REGS(r12) #ifdef CONFIG_PPC_BOOK3S_32 kuep_lock r11, r12
@@ -79,8 +61,7 @@ prepare_transfer_to_handler: /* if from kernel, check interrupted DOZE/NAP mode */ 2: - kuap_save_and_lock r11, r12, r9, r2, r6 - addi r2, r12, -THREAD + kuap_save_and_lock r11, r12, r9, r5, r6 #if defined(CONFIG_PPC_BOOK3S_32) || defined(CONFIG_E500) lwz r12,TI_LOCAL_FLAGS(r2) mtcrf 0x01,r12
diff --git a/arch/powerpc/kernel/head_32.h b/arch/powerpc/kernel/head_32.h
index ba20bfabdf63..267479072495 100644
--- a/arch/powerpc/kernel/head_32.h
+++ b/arch/powerpc/kernel/head_32.h@@ -117,6 +117,18 @@ _ASM_NOKPROBE_SYMBOL(\name\()_virt) stw r10,_TRAP(r1) SAVE_4GPRS(3, r1) SAVE_2GPRS(7, r1) + SAVE_NVGPRS(r1) + stw r2,GPR2(r1) + stw r12,_NIP(r1) + stw r9,_MSR(r1) + mfctr r0 + mfspr r10,SPRN_XER + mfspr r2,SPRN_SPRG_THREAD + stw r0,_CTR(r1) + tovirt(r2, r2) + stw r10,_XER(r1) + addi r2, r2, -THREAD + addi r3,r1,STACK_FRAME_OVERHEAD .endm .macro prepare_transfer_to_handler
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2.25.0