From c5e296f532afb411051444f64016755a07cdcd4b Mon Sep 17 00:00:00 2001 From: Anton Blanchard Date: Tue, 9 Mar 2004 15:58:13 -0800 Subject: [PATCH] [PATCH] ppc64 POWER3 segment table fix The ppc64 fix last week (enforcing permissions on the kernel when accessing userspace pages) uncovered a bug on POWER3/RS64. We werent zeroing the segment table entry before overwriting it and it was possible for the ks bit to be set on a kernel segment. The VSID mask was also changed to match reality (we only use 13 bits). --- arch/ppc64/kernel/head.S | 21 +++++++++++---------- arch/ppc64/kernel/stab.c | 5 +++++ include/asm-ppc64/mmu_context.h | 4 ++-- 3 files changed, 18 insertions(+), 12 deletions(-) diff --git a/arch/ppc64/kernel/head.S b/arch/ppc64/kernel/head.S index fef3209ec2c9..7c0ebaa4175c 100644 --- a/arch/ppc64/kernel/head.S +++ b/arch/ppc64/kernel/head.S @@ -904,12 +904,13 @@ _GLOBAL(do_stab_bolted) /* (((ea >> 28) & 0x1fff) << 15) | (ea >> 60) */ mfspr r21,DAR - rldicl r20,r21,36,32 /* Permits a full 32b of ESID */ - rldicr r20,r20,15,48 - rldicl r21,r21,4,60 - or r20,r20,r21 + rldicl r20,r21,36,51 + sldi r20,r20,15 + srdi r21,r21,60 + or r20,r20,r21 - li r21,9 /* VSID_RANDOMIZER */ + /* VSID_RANDOMIZER */ + li r21,9 sldi r21,r21,32 oris r21,r21,58231 ori r21,r21,39831 @@ -933,11 +934,11 @@ _GLOBAL(do_stab_bolted) rldicl r23,r23,57,63 cmpwi r23,0 bne 2f - ld r23,8(r21) /* Get the current vsid part of the ste */ + li r23,0 rldimi r23,r20,12,0 /* Insert the new vsid value */ std r23,8(r21) /* Put new entry back into the stab */ eieio /* Order vsid update */ - ld r23,0(r21) /* Get the esid part of the ste */ + li r23,0 mfspr r20,DAR /* Get the new esid */ rldicl r20,r20,36,28 /* Permits a full 36b of ESID */ rldimi r23,r20,28,0 /* Insert the new esid value */ @@ -971,13 +972,13 @@ _GLOBAL(do_stab_bolted) std r23,0(r21) sync - ld r23,8(r21) + li r23,0 rldimi r23,r20,12,0 std r23,8(r21) eieio - ld r23,0(r21) /* Get the esid part of the ste */ - mr r22,r23 + ld r22,0(r21) /* Get the esid part of the ste */ + li r23,0 mfspr r20,DAR /* Get the new esid */ rldicl r20,r20,36,28 /* Permits a full 32b of ESID */ rldimi r23,r20,28,0 /* Insert the new esid value */ diff --git a/arch/ppc64/kernel/stab.c b/arch/ppc64/kernel/stab.c index eab89514e4dc..6a4033784e65 100644 --- a/arch/ppc64/kernel/stab.c +++ b/arch/ppc64/kernel/stab.c @@ -88,6 +88,8 @@ static int make_ste(unsigned long stab, unsigned long esid, unsigned long vsid) for (group = 0; group < 2; group++) { for (entry = 0; entry < 8; entry++, ste++) { if (!(ste->dw0.dw0.v)) { + ste->dw0.dword0 = 0; + ste->dw1.dword1 = 0; ste->dw1.dw1.vsid = vsid; ste->dw0.dw0.esid = esid; ste->dw0.dw0.kp = 1; @@ -135,6 +137,9 @@ static int make_ste(unsigned long stab, unsigned long esid, unsigned long vsid) castout_ste->dw0.dw0.v = 0; asm volatile("sync" : : : "memory"); /* Order update */ + + castout_ste->dw0.dword0 = 0; + castout_ste->dw1.dword1 = 0; castout_ste->dw1.dw1.vsid = vsid; old_esid = castout_ste->dw0.dw0.esid; castout_ste->dw0.dw0.esid = esid; diff --git a/include/asm-ppc64/mmu_context.h b/include/asm-ppc64/mmu_context.h index 8be5b8d0a61b..2682e04f91ab 100644 --- a/include/asm-ppc64/mmu_context.h +++ b/include/asm-ppc64/mmu_context.h @@ -186,7 +186,7 @@ get_kernel_vsid( unsigned long ea ) { unsigned long ordinal, vsid; - ordinal = (((ea >> 28) & 0x1fffff) * LAST_USER_CONTEXT) | (ea >> 60); + ordinal = (((ea >> 28) & 0x1fff) * LAST_USER_CONTEXT) | (ea >> 60); vsid = (ordinal * VSID_RANDOMIZER) & VSID_MASK; ifppcdebug(PPCDBG_HTABSTRESS) { @@ -209,7 +209,7 @@ get_vsid( unsigned long context, unsigned long ea ) { unsigned long ordinal, vsid; - ordinal = (((ea >> 28) & 0x1fffff) * LAST_USER_CONTEXT) | context; + ordinal = (((ea >> 28) & 0x1fff) * LAST_USER_CONTEXT) | context; vsid = (ordinal * VSID_RANDOMIZER) & VSID_MASK; ifppcdebug(PPCDBG_HTABSTRESS) { -- 2.39.5