3.0-stable review patch. If anyone has any objections, please let me know.
------------------ From: Andrew Morton <a...@linux-foundation.org> commit 168bfeef7bba3f9784f7540b053e4ac72b769ce9 upstream. If none of the elements in scrubrates[] matches, this loop will cause __amd64_set_scrub_rate() to incorrectly use the n+1th element. As the function is designed to use the final scrubrates[] element in the case of no match, we can fix this bug by simply terminating the array search at the n-1th element. Boris: this code is fragile anyway, see here why: http://marc.info/?l=linux-kernel&m=135102834131236&w=2 It will be rewritten more robustly soonish. Reported-by: Denis Kirjanov <kirja...@gmail.com> Cc: Doug Thompson <dougthomp...@xmission.com> Signed-off-by: Andrew Morton <a...@linux-foundation.org> Signed-off-by: Borislav Petkov <borislav.pet...@amd.com> Signed-off-by: Greg Kroah-Hartman <gre...@linuxfoundation.org> --- drivers/edac/amd64_edac.c | 11 ++++------- 1 file changed, 4 insertions(+), 7 deletions(-) --- a/drivers/edac/amd64_edac.c +++ b/drivers/edac/amd64_edac.c @@ -161,8 +161,11 @@ static int __amd64_set_scrub_rate(struct * memory controller and apply to register. Search for the first * bandwidth entry that is greater or equal than the setting requested * and program that. If at last entry, turn off DRAM scrubbing. + * + * If no suitable bandwidth is found, turn off DRAM scrubbing entirely + * by falling back to the last element in scrubrates[]. */ - for (i = 0; i < ARRAY_SIZE(scrubrates); i++) { + for (i = 0; i < ARRAY_SIZE(scrubrates) - 1; i++) { /* * skip scrub rates which aren't recommended * (see F10 BKDG, F3x58) @@ -172,12 +175,6 @@ static int __amd64_set_scrub_rate(struct if (scrubrates[i].bandwidth <= new_bw) break; - - /* - * if no suitable bandwidth found, turn off DRAM scrubbing - * entirely by falling back to the last element in the - * scrubrates array. - */ } scrubval = scrubrates[i].scrubval; -- To unsubscribe from this list: send the line "unsubscribe linux-kernel" in the body of a message to majord...@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/
