linux-dev/kernel/printk, branch master

printk: Mark printk percpu data ready ro_after_init

2022-09-29T13:20:52Z

This variable cannot change post boot. Signed-off-by: Thomas Gleixner Signed-off-by: John Ogness Reviewed-by: Sergey Senozhatsky Reviewed-by: Petr Mladek Reviewed-by: Greg Kroah-Hartman Signed-off-by: Petr Mladek Link: https://lore.kernel.org/r/20220924000454.3319186-6-john.ogness@linutronix.de

printk: Remove bogus comment vs. boot consoles

2022-09-29T13:20:44Z

The comment about unregistering boot consoles is just not matching the reality. Remove it. Signed-off-by: Thomas Gleixner Signed-off-by: John Ogness Reviewed-by: Sergey Senozhatsky Reviewed-by: Petr Mladek Reviewed-by: Greg Kroah-Hartman Signed-off-by: Petr Mladek Link: https://lore.kernel.org/r/20220924000454.3319186-5-john.ogness@linutronix.de

printk: Remove write only variable nr_ext_console_drivers

2022-09-29T13:20:36Z

Commit a699449bb13b ("printk: refactor and rework printing logic") removed the need for @nr_ext_console_drivers. Remove the unneeded variable. Signed-off-by: Thomas Gleixner Signed-off-by: John Ogness Reviewed-by: Sergey Senozhatsky Reviewed-by: Petr Mladek Reviewed-by: Greg Kroah-Hartman Signed-off-by: Petr Mladek Link: https://lore.kernel.org/r/20220924000454.3319186-4-john.ogness@linutronix.de

printk: Make pr_flush() static

2022-09-29T13:20:22Z

No user outside the printk code and no reason to export this. Signed-off-by: Thomas Gleixner Signed-off-by: John Ogness Reviewed-by: Sergey Senozhatsky Reviewed-by: Petr Mladek Reviewed-by: Greg Kroah-Hartman Signed-off-by: Petr Mladek Link: https://lore.kernel.org/r/20220924000454.3319186-2-john.ogness@linutronix.de

printk: do not wait for consoles when suspended

2022-07-15T08:52:11Z

The console_stop() and console_start() functions call pr_flush(). When suspending, these functions are called by the serial subsystem while the serial port is suspended. In this scenario, if there are any pending messages, a call to pr_flush() will always result in a timeout because the serial port cannot make forward progress. This causes longer suspend and resume times. Add a check in pr_flush() so that it will immediately timeout if the consoles are suspended. Fixes: 3b604ca81202 ("printk: add pr_flush()") Reported-by: Todd Brandt Signed-off-by: John Ogness Tested-by: Todd Brandt Signed-off-by: Petr Mladek Link: https://lore.kernel.org/r/20220715061042.373640-2-john.ogness@linutronix.de

Revert "printk: add functions to prefer direct printing"

2022-06-23T16:41:40Z

This reverts commit 2bb2b7b57f81255c13f4395ea911d6bdc70c9fe2. The testing of 5.19 release candidates revealed missing synchronization between early and regular console functionality. It would be possible to start the console kthreads later as a workaround. But it is clear that console lock serialized console drivers between each other. It opens a big area of possible problems that were not considered by people involved in the development and review. printk() is crucial for debugging kernel issues and console output is very important part of it. The number of consoles is huge and a proper review would take some time. As a result it need to be reverted for 5.19. Link: https://lore.kernel.org/r/YrBdjVwBOVgLfHyb@alley Signed-off-by: Petr Mladek Link: https://lore.kernel.org/r/20220623145157.21938-7-pmladek@suse.com

Revert "printk: add kthread console printers"

2022-06-23T16:41:40Z

This reverts commit 09c5ba0aa2fcfdadb17d045c3ee6f86d69270df7. This reverts commit b87f02307d3cfbda768520f0687c51ca77e14fc3. The testing of 5.19 release candidates revealed missing synchronization between early and regular console functionality. It would be possible to start the console kthreads later as a workaround. But it is clear that console lock serialized console drivers between each other. It opens a big area of possible problems that were not considered by people involved in the development and review. printk() is crucial for debugging kernel issues and console output is very important part of it. The number of consoles is huge and a proper review would take some time. As a result it need to be reverted for 5.19. Link: https://lore.kernel.org/r/YrBdjVwBOVgLfHyb@alley Signed-off-by: Petr Mladek Link: https://lore.kernel.org/r/20220623145157.21938-6-pmladek@suse.com

Revert "printk: extend console_lock for per-console locking"

2022-06-23T16:41:40Z

This reverts commit 8e274732115f63c1d09136284431b3555bd5cc56. The testing of 5.19 release candidates revealed missing synchronization between early and regular console functionality. It would be possible to start the console kthreads later as a workaround. But it is clear that console lock serialized console drivers between each other. It opens a big area of possible problems that were not considered by people involved in the development and review. printk() is crucial for debugging kernel issues and console output is very important part of it. The number of consoles is huge and a proper review would take some time. As a result it need to be reverted for 5.19. Link: https://lore.kernel.org/r/YrBdjVwBOVgLfHyb@alley Signed-off-by: Petr Mladek Link: https://lore.kernel.org/r/20220623145157.21938-5-pmladek@suse.com

Revert "printk: remove @console_locked"

2022-06-23T16:41:40Z

This reverts commit ab406816fca009349b89cbde885daf68a8c77e33. The testing of 5.19 release candidates revealed missing synchronization between early and regular console functionality. It would be possible to start the console kthreads later as a workaround. But it is clear that console lock serialized console drivers between each other. It opens a big area of possible problems that were not considered by people involved in the development and review. printk() is crucial for debugging kernel issues and console output is very important part of it. The number of consoles is huge and a proper review would take some time. As a result it need to be reverted for 5.19. Link: https://lore.kernel.org/r/YrBdjVwBOVgLfHyb@alley Signed-off-by: Petr Mladek Link: https://lore.kernel.org/r/20220623145157.21938-4-pmladek@suse.com

Revert "printk: Block console kthreads when direct printing will be required"

2022-06-23T16:41:40Z

This reverts commit c3230283e2819a69dad2cf7a63143fde8bab8b5c. The testing of 5.19 release candidates revealed missing synchronization between early and regular console functionality. It would be possible to start the console kthreads later as a workaround. But it is clear that console lock serialized console drivers between each other. It opens a big area of possible problems that were not considered by people involved in the development and review. printk() is crucial for debugging kernel issues and console output is very important part of it. The number of consoles is huge and a proper review would take some time. As a result it need to be reverted for 5.19. Link: https://lore.kernel.org/r/YrBdjVwBOVgLfHyb@alley Signed-off-by: Petr Mladek Link: https://lore.kernel.org/r/20220623145157.21938-3-pmladek@suse.com

linux-dev/kernel/printk, branch master

printk: Mark __printk percpu data ready __ro_after_init

printk: Remove bogus comment vs. boot consoles

printk: Remove write only variable nr_ext_console_drivers

printk: Make pr_flush() static

printk: do not wait for consoles when suspended

Revert "printk: add functions to prefer direct printing"

Revert "printk: add kthread console printers"

Revert "printk: extend console_lock for per-console locking"

Revert "printk: remove @console_locked"

Revert "printk: Block console kthreads when direct printing will be required"

printk: Mark printk percpu data ready ro_after_init