aboutsummaryrefslogtreecommitdiffstats
diff options
context:
space:
mode:
authorLinus Torvalds <torvalds@linux-foundation.org>2012-02-27 00:03:16 -0500
committerLinus Torvalds <torvalds@linux-foundation.org>2012-02-27 00:03:16 -0500
commit500dd2370e77c9551ba298bdeeb91b02d8402199 (patch)
treea1e94caef4032fec934aee7da34d6551a80e7da7
parentf6bd5798f3b7583f7e984f8408ffb5b36ece174f (diff)
parent8eaffa67b43e99ae581622c5133e20b0f48bcef1 (diff)
Merge tag 'stable/for-linus-fixes-3.3-rc5' of git://git.kernel.org/pub/scm/linux/kernel/git/konrad/xen
Two fixes to fix a memory corruption bug when WC pages never get converted back to WB but end up being recycled in the general memory pool as WC. There is a better way of fixing this, but there is not enough time to do the full benchmarking to pick one of the right options - so picking the one that favors stability for right now. Signed-off-by: Konrad Rzeszutek Wilk <konrad.wilk@oracle.com> * tag 'stable/for-linus-fixes-3.3-rc5' of git://git.kernel.org/pub/scm/linux/kernel/git/konrad/xen: xen/pat: Disable PAT support for now. xen/setup: Remove redundant filtering of PTE masks.
-rw-r--r--arch/x86/xen/enlighten.c6
-rw-r--r--arch/x86/xen/mmu.c8
2 files changed, 6 insertions, 8 deletions
diff --git a/arch/x86/xen/enlighten.c b/arch/x86/xen/enlighten.c
index 12eb07bfb267..4172af8ceeb3 100644
--- a/arch/x86/xen/enlighten.c
+++ b/arch/x86/xen/enlighten.c
@@ -1141,7 +1141,9 @@ asmlinkage void __init xen_start_kernel(void)
1141 1141
1142 /* Prevent unwanted bits from being set in PTEs. */ 1142 /* Prevent unwanted bits from being set in PTEs. */
1143 __supported_pte_mask &= ~_PAGE_GLOBAL; 1143 __supported_pte_mask &= ~_PAGE_GLOBAL;
1144#if 0
1144 if (!xen_initial_domain()) 1145 if (!xen_initial_domain())
1146#endif
1145 __supported_pte_mask &= ~(_PAGE_PWT | _PAGE_PCD); 1147 __supported_pte_mask &= ~(_PAGE_PWT | _PAGE_PCD);
1146 1148
1147 __supported_pte_mask |= _PAGE_IOMAP; 1149 __supported_pte_mask |= _PAGE_IOMAP;
@@ -1204,10 +1206,6 @@ asmlinkage void __init xen_start_kernel(void)
1204 1206
1205 pgd = (pgd_t *)xen_start_info->pt_base; 1207 pgd = (pgd_t *)xen_start_info->pt_base;
1206 1208
1207 if (!xen_initial_domain())
1208 __supported_pte_mask &= ~(_PAGE_PWT | _PAGE_PCD);
1209
1210 __supported_pte_mask |= _PAGE_IOMAP;
1211 /* Don't do the full vcpu_info placement stuff until we have a 1209 /* Don't do the full vcpu_info placement stuff until we have a
1212 possible map and a non-dummy shared_info. */ 1210 possible map and a non-dummy shared_info. */
1213 per_cpu(xen_vcpu, 0) = &HYPERVISOR_shared_info->vcpu_info[0]; 1211 per_cpu(xen_vcpu, 0) = &HYPERVISOR_shared_info->vcpu_info[0];
diff --git a/arch/x86/xen/mmu.c b/arch/x86/xen/mmu.c
index 58a0e46c404d..95c1cf60c669 100644
--- a/arch/x86/xen/mmu.c
+++ b/arch/x86/xen/mmu.c
@@ -415,13 +415,13 @@ static pteval_t iomap_pte(pteval_t val)
415static pteval_t xen_pte_val(pte_t pte) 415static pteval_t xen_pte_val(pte_t pte)
416{ 416{
417 pteval_t pteval = pte.pte; 417 pteval_t pteval = pte.pte;
418 418#if 0
419 /* If this is a WC pte, convert back from Xen WC to Linux WC */ 419 /* If this is a WC pte, convert back from Xen WC to Linux WC */
420 if ((pteval & (_PAGE_PAT | _PAGE_PCD | _PAGE_PWT)) == _PAGE_PAT) { 420 if ((pteval & (_PAGE_PAT | _PAGE_PCD | _PAGE_PWT)) == _PAGE_PAT) {
421 WARN_ON(!pat_enabled); 421 WARN_ON(!pat_enabled);
422 pteval = (pteval & ~_PAGE_PAT) | _PAGE_PWT; 422 pteval = (pteval & ~_PAGE_PAT) | _PAGE_PWT;
423 } 423 }
424 424#endif
425 if (xen_initial_domain() && (pteval & _PAGE_IOMAP)) 425 if (xen_initial_domain() && (pteval & _PAGE_IOMAP))
426 return pteval; 426 return pteval;
427 427
@@ -463,7 +463,7 @@ void xen_set_pat(u64 pat)
463static pte_t xen_make_pte(pteval_t pte) 463static pte_t xen_make_pte(pteval_t pte)
464{ 464{
465 phys_addr_t addr = (pte & PTE_PFN_MASK); 465 phys_addr_t addr = (pte & PTE_PFN_MASK);
466 466#if 0
467 /* If Linux is trying to set a WC pte, then map to the Xen WC. 467 /* If Linux is trying to set a WC pte, then map to the Xen WC.
468 * If _PAGE_PAT is set, then it probably means it is really 468 * If _PAGE_PAT is set, then it probably means it is really
469 * _PAGE_PSE, so avoid fiddling with the PAT mapping and hope 469 * _PAGE_PSE, so avoid fiddling with the PAT mapping and hope
@@ -476,7 +476,7 @@ static pte_t xen_make_pte(pteval_t pte)
476 if ((pte & (_PAGE_PCD | _PAGE_PWT)) == _PAGE_PWT) 476 if ((pte & (_PAGE_PCD | _PAGE_PWT)) == _PAGE_PWT)
477 pte = (pte & ~(_PAGE_PCD | _PAGE_PWT)) | _PAGE_PAT; 477 pte = (pte & ~(_PAGE_PCD | _PAGE_PWT)) | _PAGE_PAT;
478 } 478 }
479 479#endif
480 /* 480 /*
481 * Unprivileged domains are allowed to do IOMAPpings for 481 * Unprivileged domains are allowed to do IOMAPpings for
482 * PCI passthrough, but not map ISA space. The ISA 482 * PCI passthrough, but not map ISA space. The ISA