user/sven/linux.git/kernel/printk, branch v6.6.5

Merge branch 'rework/misc-cleanups' into for-linus

2023-10-11T10:58:14Z

printk: flush consoles before checking progress

2023-10-09T08:15:04Z

Commit 9e70a5e109a4 ("printk: Add per-console suspended state") removed console lock usage during resume and replaced it with the clearly defined console_list_lock and srcu mechanisms. However, the console lock usage had an important side-effect of flushing the consoles. After its removal, consoles were no longer flushed before checking their progress. Add the console_lock/console_unlock dance to the beginning of __pr_flush() to actually flush the consoles before checking their progress. Also add comments to clarify this additional usage of the console lock. Note that console_unlock() does not guarantee flushing all messages since the commit dbdda842fe96f89 ("printk: Add console owner and waiter logic to load balance console writes"). Reported-by: Todd Brandt Closes: https://bugzilla.kernel.org/show_bug.cgi?id=217955 Fixes: 9e70a5e109a4 ("printk: Add per-console suspended state") Co-developed-by: Petr Mladek Signed-off-by: Petr Mladek Signed-off-by: John Ogness Link: https://lore.kernel.org/r/20231006082151.6969-2-pmladek@suse.com

Revert "printk: export symbols for debug modules"

2023-09-07T12:19:42Z

This reverts commit 3e00123a13d824d63072b1824c9da59cd78356d9. No, we never export random symbols for out of tree modules. Signed-off-by: Christoph Hellwig Acked-by: Greg Kroah-Hartman Acked-by: Petr Mladek Signed-off-by: Petr Mladek Link: https://lore.kernel.org/r/20230905081902.321778-1-hch@lst.de

Merge tag 'printk-for-6.6' of git://git.kernel.org/pub/scm/linux/kernel/git/printk/linux

2023-09-04T20:20:19Z

Pull printk updates from Petr Mladek: - Do not try to get the console lock when it is not need or useful in panic() - Replace the global console_suspended state by a per-console flag - Export symbols needed for dumping the raw printk buffer in panic() - Fix documentation of printf formats for integer types - Moved Sergey Senozhatsky to the reviewer role - Misc cleanups * tag 'printk-for-6.6' of git://git.kernel.org/pub/scm/linux/kernel/git/printk/linux: printk: export symbols for debug modules lib: test_scanf: Add explicit type cast to result initialization in test_number_prefix() printk: ringbuffer: Fix truncating buffer size min_t cast printk: Rename abandon_console_lock_in_panic() to other_cpu_in_panic() printk: Add per-console suspended state printk: Consolidate console deferred printing printk: Do not take console lock for console_flush_on_panic() printk: Keep non-panic-CPUs out of console lock printk: Reduce console_unblank() usage in unsafe scenarios kdb: Do not assume write() callback available docs: printk-formats: Treat char as always unsigned docs: printk-formats: Fix hex printing of signed values MAINTAINERS: adjust printk/vsprintf entries

Merge branch 'rework/misc-cleanups' into for-linus

2023-09-04T09:37:37Z

printk: export symbols for debug modules

2023-08-16T15:06:38Z

the module is out-of-tree, it saves kernel logs when panic Signed-off-by: Enlin Mu Acked-by: Petr Mladek Reviewed-by: Sergey Senozhatsky Signed-off-by: Petr Mladek Link: https://lore.kernel.org/r/20230815020711.2604939-1-yunlong.xing@unisoc.com

printk: ringbuffer: Fix truncating buffer size min_t cast

2023-08-14T11:05:22Z

If an output buffer size exceeded U16_MAX, the min_t(u16, ...) cast in copy_data() was causing writes to truncate. This manifested as output bytes being skipped, seen as %NUL bytes in pstore dumps when the available record size was larger than 65536. Fix the cast to no longer truncate the calculation. Cc: Petr Mladek Cc: Sergey Senozhatsky Cc: Steven Rostedt Cc: John Ogness Reported-by: Vijay Balakrishna Link: https://lore.kernel.org/lkml/d8bb1ec7-a4c5-43a2-9de0-9643a70b899f@linux.microsoft.com/ Fixes: b6cf8b3f3312 ("printk: add lockless ringbuffer") Cc: stable@vger.kernel.org Signed-off-by: Kees Cook Tested-by: Vijay Balakrishna Tested-by: Guilherme G. Piccoli # Steam Deck Reviewed-by: Tyler Hicks (Microsoft) Tested-by: Tyler Hicks (Microsoft) Reviewed-by: John Ogness Reviewed-by: Sergey Senozhatsky Reviewed-by: Petr Mladek Signed-off-by: Petr Mladek Link: https://lore.kernel.org/r/20230811054528.never.165-kees@kernel.org

printk: Rename abandon_console_lock_in_panic() to other_cpu_in_panic()

2023-07-20T11:06:22Z

Currently abandon_console_lock_in_panic() is only used to determine if the current CPU should immediately release the console lock because another CPU is in panic. However, later this function will be used by the CPU to immediately release other resources in this situation. Rename the function to other_cpu_in_panic(), which is a better description and does not assume it is related to the console lock. Signed-off-by: John Ogness Reviewed-by: Sergey Senozhatsky Reviewed-by: Petr Mladek Signed-off-by: Petr Mladek Link: https://lore.kernel.org/r/20230717194607.145135-8-john.ogness@linutronix.de

printk: Add per-console suspended state

2023-07-20T11:06:22Z

Currently the global @console_suspended is used to determine if consoles are in a suspended state. Its primary purpose is to allow usage of the console_lock when suspended without causing console printing. It is synchronized by the console_lock. Rather than relying on the console_lock to determine suspended state, make it an official per-console state that is set within console->flags. This allows the state to be queried via SRCU. Remove @console_suspended. Console printing will still be avoided when suspended because console_is_usable() returns false when the new suspended flag is set for that console. Signed-off-by: John Ogness Reviewed-by: Sergey Senozhatsky Reviewed-by: Petr Mladek Signed-off-by: Petr Mladek Link: https://lore.kernel.org/r/20230717194607.145135-7-john.ogness@linutronix.de

printk: Consolidate console deferred printing

2023-07-20T11:06:22Z

Printing to consoles can be deferred for several reasons: - explicitly with printk_deferred() - printk() in NMI context - recursive printk() calls The current implementation is not consistent. For printk_deferred(), irq work is scheduled twice. For NMI und recursive, panic CPU suppression and caller delays are not properly enforced. Correct these inconsistencies by consolidating the deferred printing code so that vprintk_deferred() is the top-level function for deferred printing and vprintk_emit() will perform whichever irq_work queueing is appropriate. Also add kerneldoc for wake_up_klogd() and defer_console_output() to clarify their differences and appropriate usage. Signed-off-by: John Ogness Reviewed-by: Sergey Senozhatsky Reviewed-by: Petr Mladek Signed-off-by: Petr Mladek Link: https://lore.kernel.org/r/20230717194607.145135-6-john.ogness@linutronix.de