Subject: + timer_list-correct-the-iterator-for-timer_list.patch added to -mm tree To: nzimmer@xxxxxxx,holger@xxxxxxxxxxx,john.stultz@xxxxxxxxxx,stable@xxxxxxxxxxxxxxx,tglx@xxxxxxxxxxxxx From: akpm@xxxxxxxxxxxxxxxxxxxx Date: Wed, 07 Aug 2013 14:31:14 -0700 The patch titled Subject: timer_list: correct the iterator for timer_list has been added to the -mm tree. Its filename is timer_list-correct-the-iterator-for-timer_list.patch This patch should soon appear at http://ozlabs.org/~akpm/mmots/broken-out/timer_list-correct-the-iterator-for-timer_list.patch and later at http://ozlabs.org/~akpm/mmotm/broken-out/timer_list-correct-the-iterator-for-timer_list.patch Before you just go and hit "reply", please: a) Consider who else should be cc'ed b) Prefer to cc a suitable mailing list as well c) Ideally: find the original patch on the mailing list and do a reply-to-all to that, adding suitable additional cc's *** Remember to use Documentation/SubmitChecklist when testing your code *** The -mm tree is included into linux-next and is updated there every 3-4 working days ------------------------------------------------------ From: Nathan Zimmer <nzimmer@xxxxxxx> Subject: timer_list: correct the iterator for timer_list Correct the issue with /proc/timer_list reported by Holger. When reading from the proc file with a sufficiently small buffer, 2k so not really that small, there was one could get hung trying to read the file a chunk at a time. The timer_list_start function failed to account for the possibility that the offset was adjusted outside the timer_list_next. Signed-off-by: Nathan Zimmer <nzimmer@xxxxxxx> Reported-by: Holger Hans Peter Freyther <holger@xxxxxxxxxxx> Cc: John Stultz <john.stultz@xxxxxxxxxx> Cc: Thomas Gleixner <tglx@xxxxxxxxxxxxx> Cc: <stable@xxxxxxxxxxxxxxx> # 3.10.x Signed-off-by: Andrew Morton <akpm@xxxxxxxxxxxxxxxxxxxx> --- kernel/time/timer_list.c | 41 +++++++++++++++++++++---------------- 1 file changed, 24 insertions(+), 17 deletions(-) diff -puN kernel/time/timer_list.c~timer_list-correct-the-iterator-for-timer_list kernel/time/timer_list.c --- a/kernel/time/timer_list.c~timer_list-correct-the-iterator-for-timer_list +++ a/kernel/time/timer_list.c @@ -265,10 +265,9 @@ static inline void timer_list_header(str static int timer_list_show(struct seq_file *m, void *v) { struct timer_list_iter *iter = v; - u64 now = ktime_to_ns(ktime_get()); if (iter->cpu == -1 && !iter->second_pass) - timer_list_header(m, now); + timer_list_header(m, iter->now); else if (!iter->second_pass) print_cpu(m, iter->cpu, iter->now); #ifdef CONFIG_GENERIC_CLOCKEVENTS @@ -298,33 +297,41 @@ void sysrq_timer_list_show(void) return; } -static void *timer_list_start(struct seq_file *file, loff_t *offset) +static void *move_iter(struct timer_list_iter *iter, loff_t offset) { - struct timer_list_iter *iter = file->private; - - if (!*offset) { - iter->cpu = -1; - iter->now = ktime_to_ns(ktime_get()); - } else if (iter->cpu >= nr_cpu_ids) { + for (; offset; offset--) { + iter->cpu = cpumask_next(iter->cpu, cpu_online_mask); + if (iter->cpu >= nr_cpu_ids) { #ifdef CONFIG_GENERIC_CLOCKEVENTS - if (!iter->second_pass) { - iter->cpu = -1; - iter->second_pass = true; - } else - return NULL; + if (!iter->second_pass) { + iter->cpu = -1; + iter->second_pass = true; + } else + return NULL; #else - return NULL; + return NULL; #endif + } } return iter; } +static void *timer_list_start(struct seq_file *file, loff_t *offset) +{ + struct timer_list_iter *iter = file->private; + + if (!*offset) + iter->now = ktime_to_ns(ktime_get()); + iter->cpu = -1; + iter->second_pass = false; + return move_iter(iter, *offset); +} + static void *timer_list_next(struct seq_file *file, void *v, loff_t *offset) { struct timer_list_iter *iter = file->private; - iter->cpu = cpumask_next(iter->cpu, cpu_online_mask); ++*offset; - return timer_list_start(file, offset); + return move_iter(iter, 1); } static void timer_list_stop(struct seq_file *seq, void *v) _ Patches currently in -mm which might be from nzimmer@xxxxxxx are timer_list-correct-the-iterator-for-timer_list.patch -- To unsubscribe from this list: send the line "unsubscribe stable" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html