From cf6387daf8858bdcb3e123034ca422e8979d73f1 Mon Sep 17 00:00:00 2001 From: Joachim Deguara Date: Tue, 24 Apr 2007 13:05:36 +0200 Subject: [PATCH] x86-64: make GART PTEs uncacheable This patches fixes the silent data corruption problems being seen using the GART iommu where 4kB of data where incorrect (seen mostly on Nvidia CK804 systems). This fix, to mark the memory regin the GART PTEs reside on as uncacheable, also brings the code in line with the AGP specification. Signed-off-by: Joachim Deguara Signed-off-by: Andi Kleen --- arch/x86_64/kernel/pci-gart.c | 6 +++++- 1 file changed, 5 insertions(+), 1 deletion(-) diff --git a/arch/x86_64/kernel/pci-gart.c b/arch/x86_64/kernel/pci-gart.c index 2bac8c60ad61..0bae862e9a55 100644 --- a/arch/x86_64/kernel/pci-gart.c +++ b/arch/x86_64/kernel/pci-gart.c @@ -519,7 +519,11 @@ static __init int init_k8_gatt(struct agp_kern_info *info) gatt_size = (aper_size >> PAGE_SHIFT) * sizeof(u32); gatt = (void *)__get_free_pages(GFP_KERNEL, get_order(gatt_size)); if (!gatt) - panic("Cannot allocate GATT table"); + panic("Cannot allocate GATT table"); + if (change_page_attr_addr((unsigned long)gatt, gatt_size >> PAGE_SHIFT, PAGE_KERNEL_NOCACHE)) + panic("Could not set GART PTEs to uncacheable pages"); + global_flush_tlb(); + memset(gatt, 0, gatt_size); agp_gatt_table = gatt; -- cgit v1.2.3-59-g8ed1b From 9ce883becb83190061369940de9c415595836c9b Mon Sep 17 00:00:00 2001 From: Andi Kleen Date: Tue, 24 Apr 2007 13:05:37 +0200 Subject: [PATCH] x86: Remove noreplacement option noreplacement is dangerous on modern systems because it will not replace the context switch FNSAVE with SSE aware FXSAVE. But other places in the kernel still assume SSE and do FXSAVE and the CPU will then access FXSAVE information with FNSAVE and cause corruption. Easiest way to avoid this is to remove the option. It was mostly for paranoia reasons anyways and alternative()s have been stable for some time. Thanks to Jeremy F. for reporting and helping debug it. Signed-off-by: Andi Kleen --- Documentation/x86_64/boot-options.txt | 4 ---- arch/i386/kernel/alternative.c | 21 ++------------------- 2 files changed, 2 insertions(+), 23 deletions(-) diff --git a/Documentation/x86_64/boot-options.txt b/Documentation/x86_64/boot-options.txt index 625a21db0c2a..85f51e5a749f 100644 --- a/Documentation/x86_64/boot-options.txt +++ b/Documentation/x86_64/boot-options.txt @@ -293,7 +293,3 @@ Debugging stuck (default) Miscellaneous - - noreplacement Don't replace instructions with more appropriate ones - for the CPU. This may be useful on asymmetric MP systems - where some CPUs have less capabilities than others. diff --git a/arch/i386/kernel/alternative.c b/arch/i386/kernel/alternative.c index 9eca21b49f6b..426f59b0106b 100644 --- a/arch/i386/kernel/alternative.c +++ b/arch/i386/kernel/alternative.c @@ -5,15 +5,9 @@ #include #include -static int no_replacement = 0; static int smp_alt_once = 0; static int debug_alternative = 0; -static int __init noreplacement_setup(char *s) -{ - no_replacement = 1; - return 1; -} static int __init bootonly(char *str) { smp_alt_once = 1; @@ -25,7 +19,6 @@ static int __init debug_alt(char *str) return 1; } -__setup("noreplacement", noreplacement_setup); __setup("smp-alt-boot", bootonly); __setup("debug-alternative", debug_alt); @@ -252,9 +245,6 @@ void alternatives_smp_module_add(struct module *mod, char *name, struct smp_alt_module *smp; unsigned long flags; - if (no_replacement) - return; - if (smp_alt_once) { if (boot_cpu_has(X86_FEATURE_UP)) alternatives_smp_unlock(locks, locks_end, @@ -289,7 +279,7 @@ void alternatives_smp_module_del(struct module *mod) struct smp_alt_module *item; unsigned long flags; - if (no_replacement || smp_alt_once) + if (smp_alt_once) return; spin_lock_irqsave(&smp_alt, flags); @@ -320,7 +310,7 @@ void alternatives_smp_switch(int smp) return; #endif - if (no_replacement || smp_alt_once) + if (smp_alt_once) return; BUG_ON(!smp && (num_online_cpus() > 1)); @@ -386,13 +376,6 @@ extern struct paravirt_patch __start_parainstructions[], void __init alternative_instructions(void) { unsigned long flags; - if (no_replacement) { - printk(KERN_INFO "(SMP-)alternatives turned off\n"); - free_init_pages("SMP alternatives", - (unsigned long)__smp_alt_begin, - (unsigned long)__smp_alt_end); - return; - } local_irq_save(flags); apply_alternatives(__alt_instructions, __alt_instructions_end); -- cgit v1.2.3-59-g8ed1b From 90767bd13febfdf8a5f5077e2bb975f79d6b919c Mon Sep 17 00:00:00 2001 From: Andi Kleen Date: Tue, 24 Apr 2007 13:05:37 +0200 Subject: [PATCH] x86-64: Always flush all pages in change_page_attr change_page_attr on x86-64 only flushed the TLB for pages that got reverted. That's not correct: it has to be flushed in all cases. This bug was added in some earlier changes. Just flush all pages for now. This could be done more efficiently, but for this late in the release this seem to be the best fix. Pointed out by Jan Beulich Signed-off-by: Andi Kleen --- arch/x86_64/mm/pageattr.c | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-) diff --git a/arch/x86_64/mm/pageattr.c b/arch/x86_64/mm/pageattr.c index 65c5eaa59905..081409aa3452 100644 --- a/arch/x86_64/mm/pageattr.c +++ b/arch/x86_64/mm/pageattr.c @@ -81,8 +81,8 @@ static void flush_kernel_map(void *arg) void *adr = page_address(pg); if (cpu_has_clflush) cache_flush_page(adr); - __flush_tlb_one(adr); } + __flush_tlb_all(); } static inline void flush_map(struct list_head *l) -- cgit v1.2.3-59-g8ed1b From 8689b517be3e3f65f8ba20490beccca13c5879fa Mon Sep 17 00:00:00 2001 From: Andi Kleen Date: Tue, 24 Apr 2007 13:05:37 +0200 Subject: [PATCH] i386: Fix some warnings added by earlier patch Signed-off-by: Andi Kleen --- arch/i386/kernel/nmi.c | 8 ++++---- 1 file changed, 4 insertions(+), 4 deletions(-) diff --git a/arch/i386/kernel/nmi.c b/arch/i386/kernel/nmi.c index 9f1e8c1afab7..84c3497efb60 100644 --- a/arch/i386/kernel/nmi.c +++ b/arch/i386/kernel/nmi.c @@ -126,7 +126,7 @@ int avail_to_resrv_perfctr_nmi_bit(unsigned int counter) int cpu; BUG_ON(counter > NMI_MAX_COUNTER_BITS); for_each_possible_cpu (cpu) { - if (test_bit(counter, &per_cpu(perfctr_nmi_owner, cpu))) + if (test_bit(counter, &per_cpu(perfctr_nmi_owner, cpu)[0])) return 0; } return 1; @@ -142,7 +142,7 @@ int avail_to_resrv_perfctr_nmi(unsigned int msr) BUG_ON(counter > NMI_MAX_COUNTER_BITS); for_each_possible_cpu (cpu) { - if (test_bit(counter, &per_cpu(perfctr_nmi_owner, cpu))) + if (test_bit(counter, &per_cpu(perfctr_nmi_owner, cpu)[0])) return 0; } return 1; @@ -157,7 +157,7 @@ static int __reserve_perfctr_nmi(int cpu, unsigned int msr) counter = nmi_perfctr_msr_to_bit(msr); BUG_ON(counter > NMI_MAX_COUNTER_BITS); - if (!test_and_set_bit(counter, &per_cpu(perfctr_nmi_owner, cpu))) + if (!test_and_set_bit(counter, &per_cpu(perfctr_nmi_owner, cpu)[0])) return 1; return 0; } @@ -171,7 +171,7 @@ static void __release_perfctr_nmi(int cpu, unsigned int msr) counter = nmi_perfctr_msr_to_bit(msr); BUG_ON(counter > NMI_MAX_COUNTER_BITS); - clear_bit(counter, &per_cpu(perfctr_nmi_owner, cpu)); + clear_bit(counter, &per_cpu(perfctr_nmi_owner, cpu)[0]); } int reserve_perfctr_nmi(unsigned int msr) -- cgit v1.2.3-59-g8ed1b