diff options
| author | Will Deacon <will.deacon@arm.com> | 2010-09-13 16:19:41 +0100 |
|---|---|---|
| committer | Russell King <rmk+kernel@arm.linux.org.uk> | 2010-10-04 20:57:10 +0100 |
| commit | c4e259c859538e94007d1f04a488540375189551 (patch) | |
| tree | df5485bd1184c562a11a8588915539d136e8de29 | |
| parent | 8925ec4c530094b878e7e28a1fd78e7122afd973 (diff) | |
ARM: 6386/1: flush_ptrace_access: invalidate correct I-cache alias
copy_to_user_page can be used by access_process_vm to write to an
executable page of a process using a mapping acquired by kmap.
For systems with I-cache aliasing, flushing the I-cache using the
Kernel mapping may leave stale data in the I-cache if the user
mapping is of a different colour.
This patch introduces a flush_icache_alias function to flush.c,
which calls flush_icache_range with a mapping of the specified
colour. flush_ptrace_access is then modified to call this new
function instead of coherent_kern_range in the case of an aliasing
I-cache and a non-aliasing D-cache.
Signed-off-by: Will Deacon <will.deacon@arm.com>
Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>
| -rw-r--r-- | arch/arm/mm/flush.c | 23 |
1 files changed, 20 insertions, 3 deletions
diff --git a/arch/arm/mm/flush.c b/arch/arm/mm/flush.c index 2332b774c6b..391ffae7509 100644 --- a/arch/arm/mm/flush.c +++ b/arch/arm/mm/flush.c @@ -40,6 +40,18 @@ static void flush_pfn_alias(unsigned long pfn, unsigned long vaddr) : "cc"); } +static void flush_icache_alias(unsigned long pfn, unsigned long vaddr, unsigned long len) +{ + unsigned long colour = CACHE_COLOUR(vaddr); + unsigned long offset = vaddr & (PAGE_SIZE - 1); + unsigned long to; + + set_pte_ext(TOP_PTE(ALIAS_FLUSH_START) + colour, pfn_pte(pfn, PAGE_KERNEL), 0); + to = ALIAS_FLUSH_START + (colour << PAGE_SHIFT) + offset; + flush_tlb_kernel_page(to); + flush_icache_range(to, to + len); +} + void flush_cache_mm(struct mm_struct *mm) { if (cache_is_vivt()) { @@ -90,8 +102,10 @@ void flush_cache_page(struct vm_area_struct *vma, unsigned long user_addr, unsig if (vma->vm_flags & VM_EXEC && icache_is_vivt_asid_tagged()) __flush_icache_all(); } + #else -#define flush_pfn_alias(pfn,vaddr) do { } while (0) +#define flush_pfn_alias(pfn,vaddr) do { } while (0) +#define flush_icache_alias(pfn,vaddr,len) do { } while (0) #endif static void flush_ptrace_access_other(void *args) @@ -117,10 +131,13 @@ void flush_ptrace_access(struct vm_area_struct *vma, struct page *page, return; } - /* VIPT non-aliasing cache */ + /* VIPT non-aliasing D-cache */ if (vma->vm_flags & VM_EXEC) { unsigned long addr = (unsigned long)kaddr; - __cpuc_coherent_kern_range(addr, addr + len); + if (icache_is_vipt_aliasing()) + flush_icache_alias(page_to_pfn(page), uaddr, len); + else + __cpuc_coherent_kern_range(addr, addr + len); if (cache_ops_need_broadcast()) smp_call_function(flush_ptrace_access_other, NULL, 1); |