Hi, Anton posted 4 fixes on DSCR support and all these patches are accepted in upstream kernel, 3.2.y, 3.4.y and 3.6.y stable trees.
http://git.kernel.org/?p=linux/kernel/git/torvalds/linux-2.6.git;a=commitdiff;h=1021cb268b3025573c4811f1dee4a11260c4507b http://git.kernel.org/?p=linux/kernel/git/torvalds/linux-2.6.git;a=commitdiff;h=714332858bfd40dcf8f741498336d93875c23aa7 http://git.kernel.org/?p=linux/kernel/git/torvalds/linux-2.6.git;a=commitdiff;h=1b6ca2a6fe56e7697d57348646e07df08f43b1bb http://git.kernel.org/?p=linux/kernel/git/torvalds/linux-2.6.git;a=commitdiff;h=00ca0de02f80924dfff6b4f630e1dff3db005e35 The first 2 commits are accepted in 3.0 stable tree, but last 2 patches are missing due to conflicts. Posting the back-ported patches. powerpc: Update DSCR on all CPUs when writing sysfs dscr_default Back-port upstream commit 1b6ca2a6fe56e7697d57348646e07df08f43b1bb Writing to dscr_default in sysfs doesn't actually change the DSCR - we rely on a context switch on each CPU to do the work. There is no guarantee we will get a context switch in a reasonable amount of time so fire off an IPI to force an immediate change. This issue was found with the following test case: http://ozlabs.org/~anton/junkcode/dscr_explicit_test.c Signed-off-by: Anton Blanchard <[email protected]> Cc: <stable at kernel.org> # 3.0+ Signed-off-by: Haren Myneni <[email protected]> diff -Naur linux.orig/arch/powerpc/kernel/sysfs.c linux/arch/powerpc/kernel/sysfs.c --- linux.orig/arch/powerpc/kernel/sysfs.c 2012-10-01 23:19:01.164740826 -0400 +++ linux/arch/powerpc/kernel/sysfs.c 2012-10-01 23:20:54.794742340 -0400 @@ -192,6 +192,12 @@ return sprintf(buf, "%lx\n", dscr_default); } +static void update_dscr(void *dummy) +{ + if (!current->thread.dscr_inherit) + mtspr(SPRN_DSCR, dscr_default); +} + static ssize_t __used store_dscr_default(struct sysdev_class *class, struct sysdev_class_attribute *attr, const char *buf, size_t count) @@ -204,6 +210,8 @@ return -EINVAL; dscr_default = val; + on_each_cpu(update_dscr, NULL, 1); + return count; } -- To unsubscribe from this list: send the line "unsubscribe stable" in the body of a message to [email protected] More majordomo info at http://vger.kernel.org/majordomo-info.html
