Commit eca24110 authored by Christophe Leroy's avatar Christophe Leroy Committed by Michael Ellerman
Browse files

powerpc/32: Always enable data translation on syscall entry 



If the code can use a stack in vm area, it can also use a
stack in linear space.

Simplify code by removing old non VMAP stack code on PPC32 in syscall.

That means the data translation is now re-enabled early in
syscall entry in all cases, not only when using VMAP stacks.

Signed-off-by: default avatarChristophe Leroy <christophe.leroy@csgroup.eu>
Signed-off-by: default avatarMichael Ellerman <mpe@ellerman.id.au>
Link: https://lore.kernel.org/r/412c6c1786922d991bbb89c2ad2e82cffe8ab112.1612796617.git.christophe.leroy@csgroup.eu
parent 57fdfbce

arch/powerpc/kernel/head_32.h

+1 −22
Original line number Diff line number Diff line
@@ -118,7 +118,6 @@ 
.macro SYSCALL_ENTRY trapno

	mfspr	r12,SPRN_SPRG_THREAD

	mfspr	r9, SPRN_SRR1

#ifdef CONFIG_VMAP_STACK

	mfspr	r11, SPRN_SRR0

	mtctr	r11

	andi.	r11, r9, MSR_PR
@@ -126,30 +125,16 @@ 
	lwz	r1,TASK_STACK-THREAD(r12)

	beq-	99f

	addi	r1, r1, THREAD_SIZE - INT_FRAME_SIZE

	li	r10, MSR_KERNEL & ~(MSR_IR | MSR_RI) /* can take DTLB miss */

	LOAD_REG_IMMEDIATE(r10, MSR_KERNEL & ~(MSR_IR | MSR_RI)) /* can take DTLB miss */

	mtmsr	r10

	isync

	tovirt(r12, r12)

	stw	r11,GPR1(r1)

	stw	r11,0(r1)

	mr	r11, r1

#else

	andi.	r11, r9, MSR_PR

	lwz	r11,TASK_STACK-THREAD(r12)

	beq-	99f

	addi	r11, r11, THREAD_SIZE - INT_FRAME_SIZE

	tophys(r11, r11)

	stw	r1,GPR1(r11)

	stw	r1,0(r11)

	tovirt(r1, r11)		/* set new kernel sp */

#endif

	mflr	r10

	stw	r10, _LINK(r11)

#ifdef CONFIG_VMAP_STACK

	mfctr	r10

#else

	mfspr	r10,SPRN_SRR0

#endif

	stw	r10,_NIP(r11)

	mfcr	r10

	rlwinm	r10,r10,0,4,2	/* Clear SO bit in CR */
@@ -157,11 +142,7 @@ 
#ifdef CONFIG_40x

	rlwinm	r9,r9,0,14,12		/* clear MSR_WE (necessary?) */

#else

#ifdef CONFIG_VMAP_STACK

	LOAD_REG_IMMEDIATE(r10, MSR_KERNEL & ~MSR_IR) /* can take exceptions */

#else

	LOAD_REG_IMMEDIATE(r10, MSR_KERNEL & ~(MSR_IR|MSR_DR)) /* can take exceptions */

#endif

	mtmsr	r10			/* (except for mach check in rtas) */

#endif

	lis	r10,STACK_FRAME_REGS_MARKER@ha /* exception frame marker */
@@ -190,7 +171,6 @@ 
	li	r12,-1			/* clear all pending debug events */

	mtspr	SPRN_DBSR,r12

	lis	r11,global_dbcr0@ha

	tophys(r11,r11)

	addi	r11,r11,global_dbcr0@l

	lwz	r12,0(r11)

	mtspr	SPRN_DBCR0,r12
@@ -200,7 +180,6 @@ 
#endif



3:

	tovirt_novmstack r2, r2 	/* set r2 to current */

	lis	r11, transfer_to_syscall@h

	ori	r11, r11, transfer_to_syscall@l

#ifdef CONFIG_TRACE_IRQFLAGS

arch/powerpc/kernel/head_booke.h

+0 −2
Original line number Diff line number Diff line
@@ -144,7 +144,6 @@ ALT_FTR_SECTION_END_IFSET(CPU_FTR_EMB_HV) 
	li	r12,-1			/* clear all pending debug events */

	mtspr	SPRN_DBSR,r12

	lis	r11,global_dbcr0@ha

	tophys(r11,r11)

	addi	r11,r11,global_dbcr0@l

#ifdef CONFIG_SMP

	lwz	r10, TASK_CPU(r2)
@@ -158,7 +157,6 @@ ALT_FTR_SECTION_END_IFSET(CPU_FTR_EMB_HV) 
	stw	r12,4(r11)



3:

	tovirt(r2, r2)			/* set r2 to current */

	lis	r11, transfer_to_syscall@h

	ori	r11, r11, transfer_to_syscall@l

#ifdef CONFIG_TRACE_IRQFLAGS