[RFC PATCH v1 33/41] powerpc/32: Save remaining registers in exception prolog
From: Christophe Leroy <hidden>
Date: 2021-02-09 10:11:58
Also in:
lkml
Subsystem:
linux for powerpc (32-bit and 64-bit), the rest · Maintainers:
Madhavan Srinivasan, Michael Ellerman, Linus Torvalds
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. Signed-off-by: Christophe Leroy <redacted> --- arch/powerpc/kernel/entry_32.S | 18 +++--------------- arch/powerpc/kernel/head_32.h | 12 ++++++++++++ 2 files changed, 15 insertions(+), 15 deletions(-)
diff --git a/arch/powerpc/kernel/entry_32.S b/arch/powerpc/kernel/entry_32.S
index 75ca010bd78d..fd24520b2e0c 100644
--- a/arch/powerpc/kernel/entry_32.S
+++ b/arch/powerpc/kernel/entry_32.S@@ -57,20 +57,9 @@ */ .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
@@ -80,8 +69,7 @@ prepare_transfer_to_handler: 2: /* if from kernel, check interrupted DOZE/NAP mode and * check for stack overflow */ - 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 12c39178a1d2..b29c13221baa 100644
--- a/arch/powerpc/kernel/head_32.h
+++ b/arch/powerpc/kernel/head_32.h@@ -116,6 +116,18 @@ 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 _ASM_NOKPROBE_SYMBOL(\name\()_virt) .endm
--
2.25.0