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Message-Id: <353c00af4a1eeb5d3616cb8ff0f413b7e638b20c.1550692943.git.christophe.leroy@c-s.fr>
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From:   Christophe Leroy <christophe.leroy@c-s.fr>
Subject: [PATCH v4 07/16] powerpc/mm/32s: use _PAGE_EXEC in setbat()
To:     Benjamin Herrenschmidt <benh@kernel.crashing.org>,
        Paul Mackerras <paulus@samba.org>,
        Michael Ellerman <mpe@ellerman.id.au>, j.neuschaefer@gmx.net
Cc:     linux-kernel@vger.kernel.org, linuxppc-dev@lists.ozlabs.org
Date:   Thu, 21 Feb 2019 08:04:55 +0000 (UTC)
Sender: linux-kernel-owner@vger.kernel.org
Precedence: bulk

Do not set IBAT when setbat() is called without _PAGE_EXEC

Signed-off-by: Christophe Leroy <christophe.leroy@c-s.fr>
---
 arch/powerpc/mm/ppc_mmu_32.c | 10 ++++++----
 1 file changed, 6 insertions(+), 4 deletions(-)

diff --git a/arch/powerpc/mm/ppc_mmu_32.c b/arch/powerpc/mm/ppc_mmu_32.c
index 5fc59b195fef..ff8580c6ab11 100644
--- a/arch/powerpc/mm/ppc_mmu_32.c
+++ b/arch/powerpc/mm/ppc_mmu_32.c
@@ -131,6 +131,7 @@ unsigned long __init mmu_mapin_ram(unsigned long base, unsigned long top)
  * Set up one of the I/D BAT (block address translation) register pairs.
  * The parameters are not checked; in particular size must be a power
  * of 2 between 128k and 256M.
+ * On 603+, only set IBAT when _PAGE_EXEC is set
  */
 void __init setbat(int index, unsigned long virt, phys_addr_t phys,
 		   unsigned int size, pgprot_t prot)
@@ -157,11 +158,12 @@ void __init setbat(int index, unsigned long virt, phys_addr_t phys,
 			bat[1].batu |= 1; 	/* Vp = 1 */
 		if (flags & _PAGE_GUARDED) {
 			/* G bit must be zero in IBATs */
-			bat[0].batu = bat[0].batl = 0;
-		} else {
-			/* make IBAT same as DBAT */
-			bat[0] = bat[1];
+			flags &= ~_PAGE_EXEC;
 		}
+		if (flags & _PAGE_EXEC)
+			bat[0] = bat[1];
+		else
+			bat[0].batu = bat[0].batl = 0;
 	} else {
 		/* 601 cpu */
 		if (bl > BL_8M)
-- 
2.13.3