shinys000114/linux
1
0
Fork 0
mirror of https://github.com/hardkernel/linux.git synced 2026-06-07 03:15:31 +09:00
Code Issues Packages Projects Releases Wiki Activity

x86/mm/pat: Fix L1TF stable backport for CPA, 2nd call

Browse Source 
Mostly recycling the commit log from adaba23ccd which fixed
populate_pmd, but did not fix populate_pud. The same problem exists
there.

Stable trees reverted the following patch:
  Revert "x86/mm/pat: Ensure cpa->pfn only contains page frame numbers"

    This reverts commit 87e2bd898d which is
    commit edc3b9129c upstream.

but the L1TF patch 02ff2769ed backported here

  x86/mm/pat: Make set_memory_np() L1TF safe

    commit 958f79b9ee upstream

    set_memory_np() is used to mark kernel mappings not present, but it has
    it's own open coded mechanism which does not have the L1TF protection of
    inverting the address bits.

assumed that cpa->pfn contains a PFN. With the above patch reverted
it does not, which causes the PUD to be set to an incorrect address
shifted by 12 bits, which can cause various failures.

Convert the address to a PFN before passing it to pud_pfn().

This is a 4.4 stable only patch to fix the L1TF patches backport there.

Cc: stable@vger.kernel.org # 4.4-only
Cc: Andi Kleen <ak@linux.intel.com>
Signed-off-by: Jiri Slaby <jslaby@suse.cz>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
This commit is contained in:
Jiri Slaby
2018-09-07 11:13:07 +02:00
committed by Greg Kroah-Hartman
parent 06d7a39a9c
commit 15898df477
1 changed files with 1 additions and 1 deletions
Download Patch File Download Diff File Expand all files Collapse all files

2
arch/x86/mm/pageattr.c
View File

@@ -1079,7 +1079,7 @@ static int populate_pud(struct cpa_data *cpa, unsigned long start, pgd_t *pgd,
* Map everything starting from the Gb boundary, possibly with 1G pages
*/
while (end - start >= PUD_SIZE) {
set_pud(pud, pud_mkhuge(pfn_pud(cpa->pfn,
set_pud(pud, pud_mkhuge(pfn_pud(cpa->pfn >> PAGE_SHIFT,
canon_pgprot(pud_pgprot))));
start += PUD_SIZE;