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-rw-r--r--debian/patches-rt/0003-printk-Avoid-non-panic-CPUs-writing-to-ringbuffer.patch86
1 files changed, 0 insertions, 86 deletions
diff --git a/debian/patches-rt/0003-printk-Avoid-non-panic-CPUs-writing-to-ringbuffer.patch b/debian/patches-rt/0003-printk-Avoid-non-panic-CPUs-writing-to-ringbuffer.patch
deleted file mode 100644
index d7575e9a50..0000000000
--- a/debian/patches-rt/0003-printk-Avoid-non-panic-CPUs-writing-to-ringbuffer.patch
+++ /dev/null
@@ -1,86 +0,0 @@
-From: John Ogness <john.ogness@linutronix.de>
-Date: Wed, 7 Feb 2024 14:47:01 +0106
-Subject: [PATCH 03/48] printk: Avoid non-panic CPUs writing to ringbuffer
-Origin: https://www.kernel.org/pub/linux/kernel/projects/rt/6.8/older/patches-6.8.2-rt11.tar.xz
-
-Commit 13fb0f74d702 ("printk: Avoid livelock with heavy printk
-during panic") introduced a mechanism to silence non-panic CPUs
-if too many messages are being dropped. Aside from trying to
-workaround the livelock bugs of legacy consoles, it was also
-intended to avoid losing panic messages. However, if non-panic
-CPUs are writing to the ringbuffer, then reacting to dropped
-messages is too late.
-
-Another motivation is that non-finalized messages already might
-be skipped in panic(). In other words, random messages from
-non-panic CPUs might already get lost. It is better to ignore
-all to avoid confusion.
-
-To avoid losing panic CPU messages, silence non-panic CPUs
-immediately on panic.
-
-Signed-off-by: John Ogness <john.ogness@linutronix.de>
-Reviewed-by: Petr Mladek <pmladek@suse.com>
-Link: https://lore.kernel.org/r/20240207134103.1357162-13-john.ogness@linutronix.de
-Signed-off-by: Petr Mladek <pmladek@suse.com>
-Signed-off-by: Sebastian Andrzej Siewior <bigeasy@linutronix.de>
----
- kernel/printk/printk.c | 26 ++++++--------------------
- 1 file changed, 6 insertions(+), 20 deletions(-)
-
---- a/kernel/printk/printk.c
-+++ b/kernel/printk/printk.c
-@@ -462,12 +462,6 @@ static int console_msg_format = MSG_FORM
- static DEFINE_MUTEX(syslog_lock);
-
- #ifdef CONFIG_PRINTK
--/*
-- * During panic, heavy printk by other CPUs can delay the
-- * panic and risk deadlock on console resources.
-- */
--static int __read_mostly suppress_panic_printk;
--
- DECLARE_WAIT_QUEUE_HEAD(log_wait);
- /* All 3 protected by @syslog_lock. */
- /* the next printk record to read by syslog(READ) or /proc/kmsg */
-@@ -2322,7 +2316,12 @@ asmlinkage int vprintk_emit(int facility
- if (unlikely(suppress_printk))
- return 0;
-
-- if (unlikely(suppress_panic_printk) && other_cpu_in_panic())
-+ /*
-+ * The messages on the panic CPU are the most important. If
-+ * non-panic CPUs are generating any messages, they will be
-+ * silently dropped.
-+ */
-+ if (other_cpu_in_panic())
- return 0;
-
- if (level == LOGLEVEL_SCHED) {
-@@ -2807,8 +2806,6 @@ void console_prepend_dropped(struct prin
- bool printk_get_next_message(struct printk_message *pmsg, u64 seq,
- bool is_extended, bool may_suppress)
- {
-- static int panic_console_dropped;
--
- struct printk_buffers *pbufs = pmsg->pbufs;
- const size_t scratchbuf_sz = sizeof(pbufs->scratchbuf);
- const size_t outbuf_sz = sizeof(pbufs->outbuf);
-@@ -2836,17 +2833,6 @@ bool printk_get_next_message(struct prin
- pmsg->seq = r.info->seq;
- pmsg->dropped = r.info->seq - seq;
-
-- /*
-- * Check for dropped messages in panic here so that printk
-- * suppression can occur as early as possible if necessary.
-- */
-- if (pmsg->dropped &&
-- panic_in_progress() &&
-- panic_console_dropped++ > 10) {
-- suppress_panic_printk = 1;
-- pr_warn_once("Too many dropped messages. Suppress messages on non-panic CPUs to prevent livelock.\n");
-- }
--
- /* Skip record that has level above the console loglevel. */
- if (may_suppress && suppress_message_printing(r.info->level))
- goto out;