diff options
| author | Andy Lutomirski <luto@amacapital.net> | 2014-05-05 12:19:31 -0700 |
|---|---|---|
| committer | H. Peter Anvin <hpa@linux.intel.com> | 2014-05-05 13:18:25 -0700 |
| commit | 73159fdcdb9be3eda61b846864352c29371baeb6 (patch) | |
| tree | 9856e06e22e942873f47691e198e7d8531f7db21 | |
| parent | 89ca3b881987f5a4be4c5dbaa7f0df12bbdde2fd (diff) | |
x86, mm: Ensure correct alignment of the fixmap
The early_ioremap code requires that its buffers not span a PMD
boundary. The logic for ensuring that only works if the fixmap is
aligned, so assert that it's aligned correctly.
To make this work reliably, reserve_top_address needs to be
adjusted.
Signed-off-by: Andy Lutomirski <luto@amacapital.net>
Link: http://lkml.kernel.org/r/e59a5f4362661f75dd4841fa74e1f2448045e245.1399317206.git.luto@amacapital.net
Signed-off-by: H. Peter Anvin <hpa@linux.intel.com>
| -rw-r--r-- | arch/x86/mm/ioremap.c | 6 | ||||
| -rw-r--r-- | arch/x86/mm/pgtable.c | 6 |
2 files changed, 9 insertions, 3 deletions
diff --git a/arch/x86/mm/ioremap.c b/arch/x86/mm/ioremap.c index 597ac155c91..6ef98c55a89 100644 --- a/arch/x86/mm/ioremap.c +++ b/arch/x86/mm/ioremap.c @@ -355,6 +355,12 @@ void __init early_ioremap_init(void) { pmd_t *pmd; +#ifdef CONFIG_X86_64 + BUILD_BUG_ON((fix_to_virt(0) + PAGE_SIZE) & ((1 << PMD_SHIFT) - 1)); +#else + WARN_ON((fix_to_virt(0) + PAGE_SIZE) & ((1 << PMD_SHIFT) - 1)); +#endif + early_ioremap_setup(); pmd = early_ioremap_pmd(fix_to_virt(FIX_BTMAP_BEGIN)); diff --git a/arch/x86/mm/pgtable.c b/arch/x86/mm/pgtable.c index c96314abd14..5f8bdda1d1b 100644 --- a/arch/x86/mm/pgtable.c +++ b/arch/x86/mm/pgtable.c @@ -449,9 +449,9 @@ void __init reserve_top_address(unsigned long reserve) { #ifdef CONFIG_X86_32 BUG_ON(fixmaps_set > 0); - printk(KERN_INFO "Reserving virtual address space above 0x%08x\n", - (int)-reserve); - __FIXADDR_TOP = -reserve - PAGE_SIZE; + __FIXADDR_TOP = round_down(-reserve, 1 << PMD_SHIFT) - PAGE_SIZE; + printk(KERN_INFO "Reserving virtual address space above 0x%08lx (rounded to 0x%08lx)\n", + -reserve, __FIXADDR_TOP + PAGE_SIZE); #endif } |