linux-kernel - [PATCH v2 09/10] powerpc/603: Don't worry about _PAGE

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Date:   Thu, 21 Feb 2019 10:38:01 +0000 (UTC)
From:   Christophe Leroy <christophe.leroy@....fr>
To:     Benjamin Herrenschmidt <benh@...nel.crashing.org>,
        Paul Mackerras <paulus@...ba.org>,
        Michael Ellerman <mpe@...erman.id.au>
Cc:     linux-kernel@...r.kernel.org, linuxppc-dev@...ts.ozlabs.org
Subject: [PATCH v2 09/10] powerpc/603: Don't worry about _PAGE_USER in TLB
 miss handlers

PP bits take user access into account, so no need to check _PAGE_USER
here. A DSI or ISI will be generated if needed.

Signed-off-by: Christophe Leroy <christophe.leroy@....fr>
---
 arch/powerpc/kernel/head_32.S | 12 +++---------
 1 file changed, 3 insertions(+), 9 deletions(-)

diff --git a/arch/powerpc/kernel/head_32.S b/arch/powerpc/kernel/head_32.S
index b071f328b4b0..6b5cb7551a72 100644
--- a/arch/powerpc/kernel/head_32.S
+++ b/arch/powerpc/kernel/head_32.S
@@ -503,11 +503,9 @@ InstructionTLBMiss:
 	cmplw	0,r1,r3
 #endif
 	mfspr	r2, SPRN_SPRG_PGDIR
-	li	r1,_PAGE_USER|_PAGE_PRESENT|_PAGE_EXEC /* low addresses tested as user */
+	li	r1,_PAGE_PRESENT | _PAGE_EXEC
 #if defined(CONFIG_MODULES) || defined(CONFIG_DEBUG_PAGEALLOC)
 	bge-	112f
-	mfspr	r2,SPRN_SRR1		/* and MSR_PR bit from SRR1 */
-	rlwimi	r1,r2,32-12,29,29	/* shift MSR_PR to _PAGE_USER posn */
 	lis	r2, (swapper_pg_dir - PAGE_OFFSET)@ha	/* if kernel address, use */
 	addi	r2, r2, (swapper_pg_dir - PAGE_OFFSET)@l	/* kernel page table */
 #endif
@@ -573,10 +571,8 @@ DataLoadTLBMiss:
 	lis	r1,PAGE_OFFSET@h		/* check if kernel address */
 	cmplw	0,r1,r3
 	mfspr	r2, SPRN_SPRG_PGDIR
-	li	r1,_PAGE_USER|_PAGE_PRESENT /* low addresses tested as user */
+	li	r1, _PAGE_PRESENT
 	bge-	112f
-	mfspr	r2,SPRN_SRR1		/* and MSR_PR bit from SRR1 */
-	rlwimi	r1,r2,32-12,29,29	/* shift MSR_PR to _PAGE_USER posn */
 	lis	r2, (swapper_pg_dir - PAGE_OFFSET)@ha	/* if kernel address, use */
 	addi	r2, r2, (swapper_pg_dir - PAGE_OFFSET)@l	/* kernel page table */
 112:	rlwimi	r2,r3,12,20,29		/* insert top 10 bits of address */
@@ -653,10 +649,8 @@ DataStoreTLBMiss:
 	lis	r1,PAGE_OFFSET@h		/* check if kernel address */
 	cmplw	0,r1,r3
 	mfspr	r2, SPRN_SPRG_PGDIR
-	li	r1,_PAGE_RW|_PAGE_USER|_PAGE_PRESENT /* access flags */
+	li	r1, _PAGE_RW | _PAGE_PRESENT /* access flags */
 	bge-	112f
-	mfspr	r2,SPRN_SRR1		/* and MSR_PR bit from SRR1 */
-	rlwimi	r1,r2,32-12,29,29	/* shift MSR_PR to _PAGE_USER posn */
 	lis	r2, (swapper_pg_dir - PAGE_OFFSET)@ha	/* if kernel address, use */
 	addi	r2, r2, (swapper_pg_dir - PAGE_OFFSET)@l	/* kernel page table */
 112:	rlwimi	r2,r3,12,20,29		/* insert top 10 bits of address */
-- 
2.13.3