2.6.28-stable review patch. If anyone has any objections, please let us know. ------------------ From: Suresh Siddha commit 9597134218300c045cf219be3664615e97cb239c upstream. Beschorner Daniel reported: > hwinfo problem since 2.6.28, showing this in the oops: > Corrupted page table at address 7fd04de3ec00 Also, PaX Team reported a regression with this commit: > commit 9542ada803198e6eba29d3289abb39ea82047b92 > Author: Suresh Siddha > Date: Wed Sep 24 08:53:33 2008 -0700 > > x86: track memtype for RAM in page struct This commit breaks mapping any RAM page through /dev/mem, as the reserve_memtype() was not initializing the return attribute type and as such corrupting the PTE entry that was setup with the return attribute type. Because of this bug, application mapping this RAM page through /dev/mem will die with "Corrupted page table at address xxxx" message in the kernel log and also the kernel identity mapping which maps the underlying RAM page gets converted to UC. Fix this by initializing the return attribute type before calling reserve_ram_pages_type() Reported-by: PaX Team Reported-and-tested-by: Beschorner Daniel Tested-and-Acked-by: PaX Team Signed-off-by: Suresh Siddha Signed-off-by: Venkatesh Pallipadi Signed-off-by: Ingo Molnar Signed-off-by: Greg Kroah-Hartman --- arch/x86/mm/pat.c | 6 +++--- 1 file changed, 3 insertions(+), 3 deletions(-) --- a/arch/x86/mm/pat.c +++ b/arch/x86/mm/pat.c @@ -333,6 +333,9 @@ int reserve_memtype(u64 start, u64 end, req_type & _PAGE_CACHE_MASK); } + if (new_type) + *new_type = actual_type + /* * For legacy reasons, some parts of the physical address range in the * legacy 1MB region is treated as non-RAM (even when listed as RAM in @@ -356,9 +359,6 @@ int reserve_memtype(u64 start, u64 end, new->end = end; new->type = actual_type; - if (new_type) - *new_type = actual_type; - spin_lock(&memtype_lock); if (cached_entry && start >= cached_start) -- To unsubscribe from this list: send the line "unsubscribe linux-kernel" in the body of a message to majordomo@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/