Commit cd08f109 authored by Christophe Leroy's avatar Christophe Leroy Committed by Michael Ellerman
Browse files

powerpc/32s: Enable CONFIG_VMAP_STACK 



A few changes to retrieve DAR and DSISR from struct regs
instead of retrieving them directly, as they may have
changed due to a TLB miss.

Also modifies hash_page() and friends to work with virtual
data addresses instead of physical ones. Same on load_up_fpu()
and load_up_altivec().

Signed-off-by: default avatarChristophe Leroy <christophe.leroy@c-s.fr>
[mpe: Fix tovirt_vmstack call in head_32.S to fix CHRP build]
Signed-off-by: default avatarMichael Ellerman <mpe@ellerman.id.au>
Link: https://lore.kernel.org/r/2e2509a242fd5f3e23df4a06530c18060c4d321e.1576916812.git.christophe.leroy@c-s.fr
parent 94dd54c5

arch/powerpc/kernel/entry_32.S

+1 −1
Original line number Diff line number Diff line
@@ -1339,7 +1339,7 @@ _GLOBAL(enter_rtas) 
	lis	r6,1f@ha	/* physical return address for rtas */

	addi	r6,r6,1f@l

	tophys(r6,r6)

	tophys(r7,r1)

	tophys_novmstack r7, r1

	lwz	r8,RTASENTRY(r4)

	lwz	r4,RTASBASE(r4)

	mfmsr	r9

arch/powerpc/kernel/fpu.S

+3 −0
Original line number Diff line number Diff line
@@ -94,6 +94,9 @@ END_FTR_SECTION_IFSET(CPU_FTR_VSX) 
	/* enable use of FP after return */

#ifdef CONFIG_PPC32

	mfspr	r5,SPRN_SPRG_THREAD	/* current task's THREAD (phys) */

#ifdef CONFIG_VMAP_STACK

	tovirt(r5, r5)

#endif

	lwz	r4,THREAD_FPEXC_MODE(r5)

	ori	r9,r9,MSR_FP		/* enable FP for current */

	or	r9,r9,r4

arch/powerpc/kernel/head_32.S

+13 −3
Original line number Diff line number Diff line
@@ -272,14 +272,21 @@ __secondary_hold_acknowledge: 
 */

	. = 0x200

	DO_KVM  0x200

MachineCheck:

	EXCEPTION_PROLOG_0

#ifdef CONFIG_VMAP_STACK

	li	r11, MSR_KERNEL & ~(MSR_IR | MSR_RI) /* can take DTLB miss */

	mtmsr	r11

	isync

#endif

#ifdef CONFIG_PPC_CHRP

	mfspr	r11, SPRN_SPRG_THREAD

	tovirt_vmstack r11, r11

	lwz	r11, RTAS_SP(r11)

	cmpwi	cr1, r11, 0

	bne	cr1, 7f

#endif /* CONFIG_PPC_CHRP */

	EXCEPTION_PROLOG_1

	EXCEPTION_PROLOG_1 for_rtas=1

7:	EXCEPTION_PROLOG_2

	addi	r3,r1,STACK_FRAME_OVERHEAD

#ifdef CONFIG_PPC_CHRP
@@ -294,7 +301,7 @@ __secondary_hold_acknowledge: 
	. = 0x300

	DO_KVM  0x300

DataAccess:

	EXCEPTION_PROLOG

	EXCEPTION_PROLOG handle_dar_dsisr=1

	get_and_save_dar_dsisr_on_stack	r4, r5, r11

BEGIN_MMU_FTR_SECTION

#ifdef CONFIG_PPC_KUAP
@@ -334,7 +341,7 @@ END_MMU_FTR_SECTION_IFSET(MMU_FTR_HPTE_TABLE) 
	. = 0x600

	DO_KVM  0x600

Alignment:

	EXCEPTION_PROLOG

	EXCEPTION_PROLOG handle_dar_dsisr=1

	save_dar_dsisr_on_stack r4, r5, r11

	addi	r3,r1,STACK_FRAME_OVERHEAD

	EXC_XFER_STD(0x600, alignment_exception)
@@ -645,6 +652,9 @@ handle_page_fault_tramp_1: 
handle_page_fault_tramp_2:

	EXC_XFER_LITE(0x300, handle_page_fault)



stack_overflow:

	vmap_stack_overflow_exception



AltiVecUnavailable:

	EXCEPTION_PROLOG

#ifdef CONFIG_ALTIVEC

arch/powerpc/kernel/head_32.h

+3 −1
Original line number Diff line number Diff line
@@ -38,11 +38,13 @@ 
	andi.	r11, r11, MSR_PR

.endm



.macro EXCEPTION_PROLOG_1

.macro EXCEPTION_PROLOG_1 for_rtas=0

#ifdef CONFIG_VMAP_STACK

	.ifeq	\for_rtas

	li	r11, MSR_KERNEL & ~(MSR_IR | MSR_RI) /* can take DTLB miss */

	mtmsr	r11

	isync

	.endif

	subi	r11, r1, INT_FRAME_SIZE		/* use r1 if kernel */

#else

	tophys(r11,r1)			/* use tophys(r1) if kernel */

arch/powerpc/kernel/vector.S

+3 −0
Original line number Diff line number Diff line
@@ -67,6 +67,9 @@ _GLOBAL(load_up_altivec) 
#ifdef CONFIG_PPC32

	mfspr	r5,SPRN_SPRG_THREAD		/* current task's THREAD (phys) */

	oris	r9,r9,MSR_VEC@h

#ifdef CONFIG_VMAP_STACK

	tovirt(r5, r5)

#endif

#else

	ld	r4,PACACURRENT(r13)

	addi	r5,r4,THREAD		/* Get THREAD */

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