From: Felix Fietkau Date: Sat, 18 Jul 2015 22:38:41 +0000 (+0200) Subject: MIPS: Fix sched_getaffinity with MT FPAFF enabled X-Git-Tag: v3.2.72~98 X-Git-Url: https://git.openpandora.org/cgi-bin/gitweb.cgi?p=pandora-kernel.git;a=commitdiff_plain;h=226302bdd94de8fd2a772f8c233b5e638ff56959 MIPS: Fix sched_getaffinity with MT FPAFF enabled commit 1d62d737555e1378eb62a8bba26644f7d97139d2 upstream. p->thread.user_cpus_allowed is zero-initialized and is only filled on the first sched_setaffinity call. To avoid adding overhead in the task initialization codepath, simply OR the returned mask in sched_getaffinity with p->cpus_allowed. Signed-off-by: Felix Fietkau Cc: linux-mips@linux-mips.org Patchwork: https://patchwork.linux-mips.org/patch/10740/ Signed-off-by: Ralf Baechle [bwh: Backported to 3.2: also convert from obsolete cpumask API] Signed-off-by: Ben Hutchings --- diff --git a/arch/mips/kernel/mips-mt-fpaff.c b/arch/mips/kernel/mips-mt-fpaff.c index 802e6160f37e..c7e2684a53c9 100644 --- a/arch/mips/kernel/mips-mt-fpaff.c +++ b/arch/mips/kernel/mips-mt-fpaff.c @@ -154,7 +154,7 @@ asmlinkage long mipsmt_sys_sched_getaffinity(pid_t pid, unsigned int len, unsigned long __user *user_mask_ptr) { unsigned int real_len; - cpumask_t mask; + cpumask_t allowed, mask; int retval; struct task_struct *p; @@ -173,7 +173,8 @@ asmlinkage long mipsmt_sys_sched_getaffinity(pid_t pid, unsigned int len, if (retval) goto out_unlock; - cpus_and(mask, p->thread.user_cpus_allowed, cpu_possible_map); + cpumask_or(&allowed, &p->thread.user_cpus_allowed, &p->cpus_allowed); + cpumask_and(&mask, &allowed, cpu_active_mask); out_unlock: read_unlock(&tasklist_lock);