diff options
author | Jacob Shin <jacob.shin@amd.com> | 2012-10-24 14:24:44 -0500 |
---|---|---|
committer | Ben Hutchings <ben@decadent.org.uk> | 2012-12-06 11:20:09 +0000 |
commit | 8d7a5b9d13e1681163bc7572d15e2093e3311bc7 (patch) | |
tree | 83886748727687b325dedbddac3eb170e184001c /arch/x86/mm | |
parent | 3493cfdd799c2be01fe935801fb4c99c14058e58 (diff) |
x86, mm: Find_early_table_space based on ranges that are actually being mapped
commit 844ab6f993b1d32eb40512503d35ff6ad0c57030 upstream.
Current logic finds enough space for direct mapping page tables from 0
to end. Instead, we only need to find enough space to cover mr[0].start
to mr[nr_range].end -- the range that is actually being mapped by
init_memory_mapping()
This is needed after 1bbbbe779aabe1f0768c2bf8f8c0a5583679b54a, to address
the panic reported here:
https://lkml.org/lkml/2012/10/20/160
https://lkml.org/lkml/2012/10/21/157
Signed-off-by: Jacob Shin <jacob.shin@amd.com>
Link: http://lkml.kernel.org/r/20121024195311.GB11779@jshin-Toonie
Tested-by: Tom Rini <trini@ti.com>
Signed-off-by: H. Peter Anvin <hpa@linux.intel.com>
[bwh: Backported to 3.2:
- Adjust context
- The log message format is a bit different]
Signed-off-by: Ben Hutchings <ben@decadent.org.uk>
Diffstat (limited to 'arch/x86/mm')
-rw-r--r-- | arch/x86/mm/init.c | 71 |
1 files changed, 42 insertions, 29 deletions
diff --git a/arch/x86/mm/init.c b/arch/x86/mm/init.c index 87488b93a65..7ab2eae6f8e 100644 --- a/arch/x86/mm/init.c +++ b/arch/x86/mm/init.c @@ -28,36 +28,54 @@ int direct_gbpages #endif ; -static void __init find_early_table_space(unsigned long end, int use_pse, - int use_gbpages) +struct map_range { + unsigned long start; + unsigned long end; + unsigned page_size_mask; +}; + +/* + * First calculate space needed for kernel direct mapping page tables to cover + * mr[0].start to mr[nr_range - 1].end, while accounting for possible 2M and 1GB + * pages. Then find enough contiguous space for those page tables. + */ +static void __init find_early_table_space(struct map_range *mr, int nr_range) { - unsigned long puds, pmds, ptes, tables, start = 0, good_end = end; + int i; + unsigned long puds = 0, pmds = 0, ptes = 0, tables; + unsigned long start = 0, good_end; phys_addr_t base; - puds = (end + PUD_SIZE - 1) >> PUD_SHIFT; - tables = roundup(puds * sizeof(pud_t), PAGE_SIZE); + for (i = 0; i < nr_range; i++) { + unsigned long range, extra; - if (use_gbpages) { - unsigned long extra; + range = mr[i].end - mr[i].start; + puds += (range + PUD_SIZE - 1) >> PUD_SHIFT; - extra = end - ((end>>PUD_SHIFT) << PUD_SHIFT); - pmds = (extra + PMD_SIZE - 1) >> PMD_SHIFT; - } else - pmds = (end + PMD_SIZE - 1) >> PMD_SHIFT; - - tables += roundup(pmds * sizeof(pmd_t), PAGE_SIZE); + if (mr[i].page_size_mask & (1 << PG_LEVEL_1G)) { + extra = range - ((range >> PUD_SHIFT) << PUD_SHIFT); + pmds += (extra + PMD_SIZE - 1) >> PMD_SHIFT; + } else { + pmds += (range + PMD_SIZE - 1) >> PMD_SHIFT; + } - if (use_pse) { - unsigned long extra; - - extra = end - ((end>>PMD_SHIFT) << PMD_SHIFT); + if (mr[i].page_size_mask & (1 << PG_LEVEL_2M)) { + extra = range - ((range >> PMD_SHIFT) << PMD_SHIFT); #ifdef CONFIG_X86_32 - extra += PMD_SIZE; + extra += PMD_SIZE; #endif - ptes = (extra + PAGE_SIZE - 1) >> PAGE_SHIFT; - } else - ptes = (end + PAGE_SIZE - 1) >> PAGE_SHIFT; + /* The first 2/4M doesn't use large pages. */ + if (mr[i].start < PMD_SIZE) + extra += range; + + ptes += (extra + PAGE_SIZE - 1) >> PAGE_SHIFT; + } else { + ptes += (range + PAGE_SIZE - 1) >> PAGE_SHIFT; + } + } + tables = roundup(puds * sizeof(pud_t), PAGE_SIZE); + tables += roundup(pmds * sizeof(pmd_t), PAGE_SIZE); tables += roundup(ptes * sizeof(pte_t), PAGE_SIZE); #ifdef CONFIG_X86_32 @@ -75,7 +93,8 @@ static void __init find_early_table_space(unsigned long end, int use_pse, pgt_buf_top = pgt_buf_start + (tables >> PAGE_SHIFT); printk(KERN_DEBUG "kernel direct mapping tables up to %lx @ %lx-%lx\n", - end, pgt_buf_start << PAGE_SHIFT, pgt_buf_top << PAGE_SHIFT); + mr[nr_range - 1].end, pgt_buf_start << PAGE_SHIFT, + pgt_buf_top << PAGE_SHIFT); } void __init native_pagetable_reserve(u64 start, u64 end) @@ -83,12 +102,6 @@ void __init native_pagetable_reserve(u64 start, u64 end) memblock_x86_reserve_range(start, end, "PGTABLE"); } -struct map_range { - unsigned long start; - unsigned long end; - unsigned page_size_mask; -}; - #ifdef CONFIG_X86_32 #define NR_RANGE_MR 3 #else /* CONFIG_X86_64 */ @@ -260,7 +273,7 @@ unsigned long __init_refok init_memory_mapping(unsigned long start, * nodes are discovered. */ if (!after_bootmem) - find_early_table_space(end, use_pse, use_gbpages); + find_early_table_space(mr, nr_range); for (i = 0; i < nr_range; i++) ret = kernel_physical_mapping_init(mr[i].start, mr[i].end, |