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author | Linus Torvalds <torvalds@linux-foundation.org> | 2013-05-16 01:07:53 +0400 |
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committer | Linus Torvalds <torvalds@linux-foundation.org> | 2013-05-16 01:07:53 +0400 |
commit | ae3b29e67ca361f0876dad6be2061699de95d126 (patch) | |
tree | 26063709aa45ac714b2b10e22b62d23247a5a19d /arch/x86 | |
parent | 652df602f8c5e99a3cec7d8e0c114e29d93b342f (diff) | |
parent | cf8b166d5c1c89aad6c436a954fa40fd18a75bfb (diff) | |
download | linux-ae3b29e67ca361f0876dad6be2061699de95d126.tar.xz |
Merge branch 'x86-urgent-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip
Pull x86 fixes from Thomas Gleixner:
- Fix for a CPU hot-add deadlock in microcode update code
- Fix for idle consolidation fallout
- Documentation update for initial kernel direct mapping
* 'x86-urgent-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip:
x86/mm: Add missing comments for initial kernel direct mapping
x86/microcode: Add local mutex to fix physical CPU hot-add deadlock
x86: Fix idle consolidation fallout
Diffstat (limited to 'arch/x86')
-rw-r--r-- | arch/x86/kernel/microcode_intel_early.c | 5 | ||||
-rw-r--r-- | arch/x86/kernel/process.c | 5 | ||||
-rw-r--r-- | arch/x86/mm/init.c | 19 |
3 files changed, 23 insertions, 6 deletions
diff --git a/arch/x86/kernel/microcode_intel_early.c b/arch/x86/kernel/microcode_intel_early.c index d893e8ed8ac9..2e9e12871c2b 100644 --- a/arch/x86/kernel/microcode_intel_early.c +++ b/arch/x86/kernel/microcode_intel_early.c @@ -487,6 +487,7 @@ static inline void show_saved_mc(void) #endif #if defined(CONFIG_MICROCODE_INTEL_EARLY) && defined(CONFIG_HOTPLUG_CPU) +static DEFINE_MUTEX(x86_cpu_microcode_mutex); /* * Save this mc into mc_saved_data. So it will be loaded early when a CPU is * hot added or resumes. @@ -507,7 +508,7 @@ int save_mc_for_early(u8 *mc) * Hold hotplug lock so mc_saved_data is not accessed by a CPU in * hotplug. */ - cpu_hotplug_driver_lock(); + mutex_lock(&x86_cpu_microcode_mutex); mc_saved_count_init = mc_saved_data.mc_saved_count; mc_saved_count = mc_saved_data.mc_saved_count; @@ -544,7 +545,7 @@ int save_mc_for_early(u8 *mc) } out: - cpu_hotplug_driver_unlock(); + mutex_unlock(&x86_cpu_microcode_mutex); return ret; } diff --git a/arch/x86/kernel/process.c b/arch/x86/kernel/process.c index 607af0d4d5ef..4e7a37ff03ab 100644 --- a/arch/x86/kernel/process.c +++ b/arch/x86/kernel/process.c @@ -312,6 +312,8 @@ void arch_cpu_idle(void) { if (cpuidle_idle_call()) x86_idle(); + else + local_irq_enable(); } /* @@ -368,9 +370,6 @@ void amd_e400_remove_cpu(int cpu) */ static void amd_e400_idle(void) { - if (need_resched()) - return; - if (!amd_e400_c1e_detected) { u32 lo, hi; diff --git a/arch/x86/mm/init.c b/arch/x86/mm/init.c index fdc5dca14fb3..eaac1743def7 100644 --- a/arch/x86/mm/init.c +++ b/arch/x86/mm/init.c @@ -359,7 +359,17 @@ unsigned long __init_refok init_memory_mapping(unsigned long start, } /* - * would have hole in the middle or ends, and only ram parts will be mapped. + * We need to iterate through the E820 memory map and create direct mappings + * for only E820_RAM and E820_KERN_RESERVED regions. We cannot simply + * create direct mappings for all pfns from [0 to max_low_pfn) and + * [4GB to max_pfn) because of possible memory holes in high addresses + * that cannot be marked as UC by fixed/variable range MTRRs. + * Depending on the alignment of E820 ranges, this may possibly result + * in using smaller size (i.e. 4K instead of 2M or 1G) page tables. + * + * init_mem_mapping() calls init_range_memory_mapping() with big range. + * That range would have hole in the middle or ends, and only ram parts + * will be mapped in init_range_memory_mapping(). */ static unsigned long __init init_range_memory_mapping( unsigned long r_start, @@ -419,6 +429,13 @@ void __init init_mem_mapping(void) max_pfn_mapped = 0; /* will get exact value next */ min_pfn_mapped = real_end >> PAGE_SHIFT; last_start = start = real_end; + + /* + * We start from the top (end of memory) and go to the bottom. + * The memblock_find_in_range() gets us a block of RAM from the + * end of RAM in [min_pfn_mapped, max_pfn_mapped) used as new pages + * for page table. + */ while (last_start > ISA_END_ADDRESS) { if (last_start > step_size) { start = round_down(last_start - 1, step_size); |