mirror of
https://git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux.git
synced 2026-08-31 14:04:27 -04:00
b0546776ad
Pull printk updates from Petr Mladek:
"Improve the behavior during panic. The issues were found when testing
the ongoing changes introducing atomic consoles and printk kthreads:
- pr_flush() has to wait for the last reserved record instead of the
last finalized one. Note that records are finalized in random order
when generated by more CPUs in parallel.
- Ignore non-finalized records during panic(). Messages printed on
panic-CPU are always finalized. Messages printed by other CPUs
might never be finalized when the CPUs get stopped.
- Block new printk() calls on non-panic CPUs completely. Backtraces
are printed before entering the panic mode. Later messages would
just mess information printed by the panic CPU.
- Do not take console_lock in console_flush_on_panic() at all. The
original code did try_lock()/console_unlock(). The unlock part
might cause a deadlock when panic() happened in a scheduler code.
- Fix conversion of 64-bit sequence number for 32-bit atomic
operations"
* tag 'printk-for-6.9' of git://git.kernel.org/pub/scm/linux/kernel/git/printk/linux:
dump_stack: Do not get cpu_sync for panic CPU
panic: Flush kernel log buffer at the end
printk: Avoid non-panic CPUs writing to ringbuffer
printk: Disable passing console lock owner completely during panic()
printk: ringbuffer: Skip non-finalized records in panic
printk: Wait for all reserved records with pr_flush()
printk: ringbuffer: Cleanup reader terminology
printk: Add this_cpu_in_panic()
printk: For @suppress_panic_printk check for other CPU in panic
printk: ringbuffer: Clarify special lpos values
printk: ringbuffer: Do not skip non-finalized records with prb_next_seq()
printk: Use prb_first_seq() as base for 32bit seq macros
printk: Adjust mapping for 32bit seq macros
printk: nbcon: Relocate 32bit seq macros
Linux kernel
============
There are several guides for kernel developers and users. These guides can
be rendered in a number of formats, like HTML and PDF. Please read
Documentation/admin-guide/README.rst first.
In order to build the documentation, use ``make htmldocs`` or
``make pdfdocs``. The formatted documentation can also be read online at:
https://www.kernel.org/doc/html/latest/
There are various text files in the Documentation/ subdirectory,
several of them using the ReStructured Text markup notation.
Please read the Documentation/process/changes.rst file, as it contains the
requirements for building and running the kernel, and information about
the problems which may result by upgrading your kernel.