| lists.openwall.net | lists / announce owl-users owl-dev john-users john-dev passwdqc-users yescrypt popa3d-users / oss-security kernel-hardening musl sabotage tlsify passwords / crypt-dev xvendor / Bugtraq Full-Disclosure linux-kernel linux-netdev linux-ext4 linux-hardening linux-cve-announce PHC | |
|
Open Source and information security mailing list archives
| ||
|
Message-Id: <20141222101450.D7DD11A5E15@localhost.localdomain> Date: Mon, 22 Dec 2014 11:14:50 +0100 (CET) From: Christophe Leroy <christophe.leroy@....fr> To: Benjamin Herrenschmidt <benh@...nel.crashing.org>, Paul Mackerras <paulus@...ba.org>, Michael Ellerman <mpe@...erman.id.au>, scottwood@...escale.com CC: linux-kernel@...r.kernel.org, linuxppc-dev@...ts.ozlabs.org, Joakim Tjernlund <joakim.tjernlund@...nsmode.se> Subject: [PATCH v3 2/2] powerpc/8xx: use _PAGE_RO instead of _PAGE_RW On powerpc 8xx, in TLB entries, 0x400 bit is set to 1 for read-only pages and is set to 0 for RW pages. So we should use _PAGE_RO instead of _PAGE_RW Signed-off-by: Christophe Leroy <christophe.leroy@....fr> --- v2 is a complete rework compared to v1 v3: fixing pte_update() and comments arch/powerpc/include/asm/pgtable-ppc32.h | 5 +++-- arch/powerpc/include/asm/pte-8xx.h | 9 ++++----- arch/powerpc/kernel/head_8xx.S | 3 --- 3 files changed, 7 insertions(+), 10 deletions(-) diff --git a/arch/powerpc/include/asm/pgtable-ppc32.h b/arch/powerpc/include/asm/pgtable-ppc32.h index caf094a..b4e0c3b 100644 --- a/arch/powerpc/include/asm/pgtable-ppc32.h +++ b/arch/powerpc/include/asm/pgtable-ppc32.h @@ -178,9 +178,10 @@ static inline unsigned long pte_update(pte_t *p, andc %1,%0,%5\n\ or %1,%1,%6\n\ /* 0x200 == Extended encoding, bit 22 */ \ - /* Bit 22 has to be 1 if neither _PAGE_USER nor _PAGE_RW are set */ \ + /* Bit 22 has to be 1 when _PAGE_USER is unset and _PAGE_RO is set */ \ rlwimi %1,%1,32-2,0x200\n /* get _PAGE_USER */ \ - rlwinm %3,%1,32-1,0x200\n /* get _PAGE_RW */ \ + rlwinm %3,%1,32-1,0x200\n /* get _PAGE_RO */ \ + xori %3,%3,0x200\n \ or %1,%3,%1\n\ xori %1,%1,0x200\n" " stwcx. %1,0,%4\n\ diff --git a/arch/powerpc/include/asm/pte-8xx.h b/arch/powerpc/include/asm/pte-8xx.h index daa4616..eb6edb4 100644 --- a/arch/powerpc/include/asm/pte-8xx.h +++ b/arch/powerpc/include/asm/pte-8xx.h @@ -46,9 +46,9 @@ * require a TLB exception handler change. It is assumed unused bits * are always zero. */ -#define _PAGE_RW 0x0400 /* lsb PP bits, inverted in HW */ +#define _PAGE_RO 0x0400 /* lsb PP bits */ #define _PAGE_USER 0x0800 /* msb PP bits */ -/* set when neither _PAGE_USER nor _PAGE_RW are set */ +/* set when _PAGE_USER is unset and _PAGE_RO is set */ #define _PAGE_KNLRO 0x0200 #define _PMD_PRESENT 0x0001 @@ -62,9 +62,8 @@ #define PTE_ATOMIC_UPDATES 1 /* We need to add _PAGE_SHARED to kernel pages */ -#define _PAGE_KERNEL_RO (_PAGE_SHARED | _PAGE_KNLRO) -#define _PAGE_KERNEL_ROX (_PAGE_EXEC | _PAGE_KNLRO) -#define _PAGE_KERNEL_RW (_PAGE_DIRTY | _PAGE_RW | _PAGE_HWWRITE) +#define _PAGE_KERNEL_RO (_PAGE_SHARED | _PAGE_RO | _PAGE_KNLRO) +#define _PAGE_KERNEL_ROX (_PAGE_EXEC | _PAGE_RO | _PAGE_KNLRO) #endif /* __KERNEL__ */ #endif /* _ASM_POWERPC_PTE_8xx_H */ diff --git a/arch/powerpc/kernel/head_8xx.S b/arch/powerpc/kernel/head_8xx.S index 3d4b8ee..807b0db 100644 --- a/arch/powerpc/kernel/head_8xx.S +++ b/arch/powerpc/kernel/head_8xx.S @@ -441,9 +441,6 @@ DataStoreTLBMiss: and r11, r11, r10 rlwimi r10, r11, 0, _PAGE_PRESENT #endif - /* invert RW */ - xori r10, r10, _PAGE_RW - /* The Linux PTE won't go exactly into the MMU TLB. * Software indicator bits 22 and 28 must be clear. * Software indicator bits 24, 25, 26, and 27 must be -- 2.1.0 -- To unsubscribe from this list: send the line "unsubscribe linux-kernel" in the body of a message to majordomo@...r.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/
Powered by blists - more mailing lists