diff options
Diffstat (limited to 'debian/patches-rt/0010-printk-ringbuffer-Skip-non-finalized-records-in-pani.patch')
| -rw-r--r-- | debian/patches-rt/0010-printk-ringbuffer-Skip-non-finalized-records-in-pani.patch | 67 |
1 files changed, 0 insertions, 67 deletions
diff --git a/debian/patches-rt/0010-printk-ringbuffer-Skip-non-finalized-records-in-pani.patch b/debian/patches-rt/0010-printk-ringbuffer-Skip-non-finalized-records-in-pani.patch deleted file mode 100644 index a92123216f..0000000000 --- a/debian/patches-rt/0010-printk-ringbuffer-Skip-non-finalized-records-in-pani.patch +++ /dev/null @@ -1,67 +0,0 @@ -From: John Ogness <john.ogness@linutronix.de> -Date: Fri, 13 Oct 2023 10:23:11 +0000 -Subject: [PATCH 10/50] printk: ringbuffer: Skip non-finalized records in panic -Origin: https://www.kernel.org/pub/linux/kernel/projects/rt/6.7/older/patches-6.7-rt6.tar.xz - -Normally a reader will stop once reaching a non-finalized -record. However, when a panic happens, writers from other CPUs -(or an interrupted context on the panic CPU) may have been -writing a record and were unable to finalize it. The panic CPU -will reserve/commit/finalize its panic records, but these will -be located after the non-finalized records. This results in -panic() not flushing the panic messages. - -Extend _prb_read_valid() to skip over non-finalized records if -on the panic CPU. - -Fixes: 896fbe20b4e2 ("printk: use the lockless ringbuffer") -Signed-off-by: John Ogness <john.ogness@linutronix.de> -Signed-off-by: Sebastian Andrzej Siewior <bigeasy@linutronix.de> ---- - kernel/printk/printk_ringbuffer.c | 28 ++++++++++++++++++++++++++-- - 1 file changed, 26 insertions(+), 2 deletions(-) - ---- a/kernel/printk/printk_ringbuffer.c -+++ b/kernel/printk/printk_ringbuffer.c -@@ -2107,6 +2107,10 @@ u64 prb_next_reserve_seq(struct printk_r - * - * On failure @seq is updated to a record that is not yet available to the - * reader, but it will be the next record available to the reader. -+ * -+ * Note: When the current CPU is in panic, this function will skip over any -+ * non-existent/non-finalized records in order to allow the panic CPU -+ * to print any and all records that have been finalized. - */ - static bool _prb_read_valid(struct printk_ringbuffer *rb, u64 *seq, - struct printk_record *r, unsigned int *line_count) -@@ -2129,8 +2133,28 @@ static bool _prb_read_valid(struct print - (*seq)++; - - } else { -- /* Non-existent/non-finalized record. Must stop. */ -- return false; -+ /* -+ * Non-existent/non-finalized record. Must stop. -+ * -+ * For panic situations it cannot be expected that -+ * non-finalized records will become finalized. But -+ * there may be other finalized records beyond that -+ * need to be printed for a panic situation. If this -+ * is the panic CPU, skip this -+ * non-existent/non-finalized record unless it is -+ * at or beyond the head, in which case it is not -+ * possible to continue. -+ * -+ * Note that new messages printed on panic CPU are -+ * finalized when we are here. The only exception -+ * might be the last message without trailing newline. -+ * But it would have the sequence number returned -+ * by "prb_next_reserve_seq() - 1". -+ */ -+ if (this_cpu_in_panic() && ((*seq + 1) < prb_next_reserve_seq(rb))) -+ (*seq)++; -+ else -+ return false; - } - } - |