Commit f5007dbf authored by Christophe Leroy's avatar Christophe Leroy Committed by Michael Ellerman
Browse files

powerpc/booke: Avoid link stack corruption in several places 



Use bcl 20,31,+4 instead of bl in order to preserve link stack.

See commit c974809a ("powerpc/vdso: Avoid link stack corruption
in __get_datapage()") for details.

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/e9fbc285eceb720e6c0e032ef47fe8b05f669b48.1629791751.git.christophe.leroy@csgroup.eu
parent 113ec9cc

arch/powerpc/include/asm/ppc_asm.h

+1 −1
Original line number Original line Diff line number Diff line
@@ -260,7 +260,7 @@ GLUE(.,name): 




/* Be careful, this will clobber the lr register. */

/* Be careful, this will clobber the lr register. */

#define LOAD_REG_ADDR_PIC(reg, name)		\

#define LOAD_REG_ADDR_PIC(reg, name)		\

	bl	0f;				\

	bcl	20,31,$+4;			\

0:	mflr	reg;				\

0:	mflr	reg;				\

	addis	reg,reg,(name - 0b)@ha;		\

	addis	reg,reg,(name - 0b)@ha;		\

	addi	reg,reg,(name - 0b)@l;

	addi	reg,reg,(name - 0b)@l;

arch/powerpc/kernel/exceptions-64e.S

+3 −3
Original line number Original line Diff line number Diff line
@@ -1127,7 +1127,7 @@ found_iprot: 
 * r3 = MAS0_TLBSEL (for the iprot array)

 * r3 = MAS0_TLBSEL (for the iprot array)

 * r4 = SPRN_TLBnCFG

 * r4 = SPRN_TLBnCFG

 */

 */

	bl	invstr				/* Find our address */

	bcl	20,31,$+4			/* Find our address */

invstr:	mflr	r6				/* Make it accessible */

invstr:	mflr	r6				/* Make it accessible */

	mfmsr	r7

	mfmsr	r7

	rlwinm	r5,r7,27,31,31			/* extract MSR[IS] */

	rlwinm	r5,r7,27,31,31			/* extract MSR[IS] */
@@ -1196,7 +1196,7 @@ skpinv: addi r6,r6,1 /* Increment */ 
	mfmsr	r6

	mfmsr	r6

	xori	r6,r6,MSR_IS

	xori	r6,r6,MSR_IS

	mtspr	SPRN_SRR1,r6

	mtspr	SPRN_SRR1,r6

	bl	1f		/* Find our address */

	bcl	20,31,$+4	/* Find our address */

1:	mflr	r6

1:	mflr	r6

	addi	r6,r6,(2f - 1b)

	addi	r6,r6,(2f - 1b)

	mtspr	SPRN_SRR0,r6

	mtspr	SPRN_SRR0,r6
@@ -1256,7 +1256,7 @@ skpinv: addi r6,r6,1 /* Increment */ 
 * r4 = MAS0 w/TLBSEL & ESEL for the temp mapping

 * r4 = MAS0 w/TLBSEL & ESEL for the temp mapping

 */

 */

	/* Now we branch the new virtual address mapped by this entry */

	/* Now we branch the new virtual address mapped by this entry */

	bl	1f		/* Find our address */

	bcl	20,31,$+4	/* Find our address */

1:	mflr	r6

1:	mflr	r6

	addi	r6,r6,(2f - 1b)

	addi	r6,r6,(2f - 1b)

	tovirt(r6,r6)

	tovirt(r6,r6)

arch/powerpc/kernel/fsl_booke_entry_mapping.S

+4 −4
Original line number Original line Diff line number Diff line 
/* SPDX-License-Identifier: GPL-2.0 */

/* SPDX-License-Identifier: GPL-2.0 */





/* 1. Find the index of the entry we're executing in */

/* 1. Find the index of the entry we're executing in */

	bl	invstr				/* Find our address */

	bcl	20,31,$+4				/* Find our address */

invstr:	mflr	r6				/* Make it accessible */

invstr:	mflr	r6				/* Make it accessible */

	mfmsr	r7

	mfmsr	r7

	rlwinm	r4,r7,27,31,31			/* extract MSR[IS] */

	rlwinm	r4,r7,27,31,31			/* extract MSR[IS] */
@@ -85,7 +85,7 @@ skpinv: addi r6,r6,1 /* Increment */ 
	addi	r6,r6,10

	addi	r6,r6,10

	slw	r6,r8,r6	/* convert to mask */

	slw	r6,r8,r6	/* convert to mask */





	bl	1f		/* Find our address */

	bcl	20,31,$+4	/* Find our address */

1:	mflr	r7

1:	mflr	r7





	mfspr	r8,SPRN_MAS3

	mfspr	r8,SPRN_MAS3
@@ -117,7 +117,7 @@ skpinv: addi r6,r6,1 /* Increment */ 




	xori	r6,r4,1

	xori	r6,r4,1

	slwi	r6,r6,5		/* setup new context with other address space */

	slwi	r6,r6,5		/* setup new context with other address space */

	bl	1f		/* Find our address */

	bcl	20,31,$+4	/* Find our address */

1:	mflr	r9

1:	mflr	r9

	rlwimi	r7,r9,0,20,31

	rlwimi	r7,r9,0,20,31

	addi	r7,r7,(2f - 1b)

	addi	r7,r7,(2f - 1b)
@@ -207,7 +207,7 @@ next_tlb_setup: 




	lis	r7,MSR_KERNEL@h

	lis	r7,MSR_KERNEL@h

	ori	r7,r7,MSR_KERNEL@l

	ori	r7,r7,MSR_KERNEL@l

	bl	1f			/* Find our address */

	bcl	20,31,$+4		/* Find our address */

1:	mflr	r9

1:	mflr	r9

	rlwimi	r6,r9,0,20,31

	rlwimi	r6,r9,0,20,31

	addi	r6,r6,(2f - 1b)

	addi	r6,r6,(2f - 1b)

arch/powerpc/kernel/head_44x.S

+3 −3
Original line number Original line Diff line number Diff line
@@ -70,7 +70,7 @@ _ENTRY(_start); 
 * address.

 * address.

 * r21 will be loaded with the physical runtime address of _stext

 * r21 will be loaded with the physical runtime address of _stext

 */

 */

	bl	0f				/* Get our runtime address */

	bcl	20,31,$+4			/* Get our runtime address */

0:	mflr	r21				/* Make it accessible */

0:	mflr	r21				/* Make it accessible */

	addis	r21,r21,(_stext - 0b)@ha

	addis	r21,r21,(_stext - 0b)@ha

	addi	r21,r21,(_stext - 0b)@l 	/* Get our current runtime base */

	addi	r21,r21,(_stext - 0b)@l 	/* Get our current runtime base */
@@ -853,7 +853,7 @@ _GLOBAL(init_cpu_state) 
wmmucr:	mtspr	SPRN_MMUCR,r3			/* Put MMUCR */

wmmucr:	mtspr	SPRN_MMUCR,r3			/* Put MMUCR */

	sync

	sync





	bl	invstr				/* Find our address */

	bcl	20,31,$+4			/* Find our address */

invstr:	mflr	r5				/* Make it accessible */

invstr:	mflr	r5				/* Make it accessible */

	tlbsx	r23,0,r5			/* Find entry we are in */

	tlbsx	r23,0,r5			/* Find entry we are in */

	li	r4,0				/* Start at TLB entry 0 */

	li	r4,0				/* Start at TLB entry 0 */
@@ -1045,7 +1045,7 @@ head_start_47x: 
	sync

	sync





	/* Find the entry we are running from */

	/* Find the entry we are running from */

	bl	1f

	bcl	20,31,$+4

1:	mflr	r23

1:	mflr	r23

	tlbsx	r23,0,r23

	tlbsx	r23,0,r23

	tlbre	r24,r23,0

	tlbre	r24,r23,0

arch/powerpc/kernel/head_fsl_booke.S

+3 −3
Original line number Original line Diff line number Diff line
@@ -79,7 +79,7 @@ _ENTRY(_start); 
	mr	r23,r3

	mr	r23,r3

	mr	r25,r4

	mr	r25,r4





	bl	0f

	bcl	20,31,$+4

0:	mflr	r8

0:	mflr	r8

	addis	r3,r8,(is_second_reloc - 0b)@ha

	addis	r3,r8,(is_second_reloc - 0b)@ha

	lwz	r19,(is_second_reloc - 0b)@l(r3)

	lwz	r19,(is_second_reloc - 0b)@l(r3)
@@ -1132,7 +1132,7 @@ _GLOBAL(switch_to_as1) 
	bne	1b

	bne	1b





	/* Get the tlb entry used by the current running code */

	/* Get the tlb entry used by the current running code */

	bl	0f

	bcl	20,31,$+4

0:	mflr	r4

0:	mflr	r4

	tlbsx	0,r4

	tlbsx	0,r4
@@ -1166,7 +1166,7 @@ _GLOBAL(switch_to_as1) 
_GLOBAL(restore_to_as0)

_GLOBAL(restore_to_as0)

	mflr	r0

	mflr	r0





	bl	0f

	bcl	20,31,$+4

0:	mflr	r9

0:	mflr	r9

	addi	r9,r9,1f - 0b

	addi	r9,r9,1f - 0b