mirror of
https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git
synced 2024-10-31 16:38:12 +00:00
printk fixes for 5.19-rc3
-----BEGIN PGP SIGNATURE----- iQIzBAABCAAdFiEESH4wyp42V4tXvYsjUqAMR0iAlPIFAmKsk94ACgkQUqAMR0iA lPKp9w/7BCovpkGiiQT1ZDSq2UVOgwpkQB8fcbGgd+7YfEVU/ILR4mRjEMfgb4CS 66T9Mgt738X6U9rmUGLRmnS21sMITRLTebBOFXAKphtT8kGyrs0JDC+8YnTTznel 892wUT4G149H2s7op3hEjnCJfxYTH0gtmRrFN30QTKXnEyCQ0AbSsVhT4uczVvgj YNur93CyR/Bh1/BtyKwe5CbDpoAPrDyGZbY2cWMWW14Enley2/8BUezlXhP8ybeU n4eQpaIu+05hzI54f3B1PelY1Ky/d2KwAXxQpQe2NU1OvXui6xlTas1aNQyBtMmF pBKCiXR+M3kT/LXambZxoAEbGEmIE01Z1ZwSuOJw54p/P8DDwOQj+HGgYCMGtTBs P3zeQ12+ir1wjz7OVAOpj53Zhb0g7g9DfmRaw1V5CSeMcptJhTcH5Jzn3uHqr0hy 3y6rculrODINzWldiiEVfPKzHrHpcU6H5fHDpjXyUAZ16mKxW6WSGklC+ckoOmRS pklCvJpJG/ZbzsXqSTgNOmDSLGZcB3OklJxZqzoX/nbmYl3EAXA4qmELIgaq6Et7 g8opDAAqXrmiLtI79KDTlEWRgkQh5h9Mkave8sm73NKwovoh58jNC0sxFyFDN442 Hq33nca4HHf91Orl8XmaHkK7/LmgT8T4BDekMN1b0buq2YSr2bg= =iiXX -----END PGP SIGNATURE----- Merge tag 'printk-for-5.19-rc3' of git://git.kernel.org/pub/scm/linux/kernel/git/printk/linux Pull printk fixes from Petr Mladek: "Make the global console_sem available for CPU that is handling panic() or shutdown. This is an old problem when an existing console lock owner might block console output, but it became more visible with the kthreads" * tag 'printk-for-5.19-rc3' of git://git.kernel.org/pub/scm/linux/kernel/git/printk/linux: printk: Wait for the global console lock when the system is going down printk: Block console kthreads when direct printing will be required
This commit is contained in:
commit
93d17c1c8c
6 changed files with 50 additions and 1 deletions
|
@ -173,6 +173,7 @@ extern void printk_prefer_direct_enter(void);
|
|||
extern void printk_prefer_direct_exit(void);
|
||||
|
||||
extern bool pr_flush(int timeout_ms, bool reset_on_progress);
|
||||
extern void try_block_console_kthreads(int timeout_ms);
|
||||
|
||||
/*
|
||||
* Please don't use printk_ratelimit(), because it shares ratelimiting state
|
||||
|
@ -237,6 +238,10 @@ static inline bool pr_flush(int timeout_ms, bool reset_on_progress)
|
|||
return true;
|
||||
}
|
||||
|
||||
static inline void try_block_console_kthreads(int timeout_ms)
|
||||
{
|
||||
}
|
||||
|
||||
static inline int printk_ratelimit(void)
|
||||
{
|
||||
return 0;
|
||||
|
|
|
@ -297,6 +297,7 @@ void panic(const char *fmt, ...)
|
|||
* unfortunately means it may not be hardened to work in a
|
||||
* panic situation.
|
||||
*/
|
||||
try_block_console_kthreads(10000);
|
||||
smp_send_stop();
|
||||
} else {
|
||||
/*
|
||||
|
@ -304,6 +305,7 @@ void panic(const char *fmt, ...)
|
|||
* kmsg_dump, we will need architecture dependent extra
|
||||
* works in addition to stopping other CPUs.
|
||||
*/
|
||||
try_block_console_kthreads(10000);
|
||||
crash_smp_send_stop();
|
||||
}
|
||||
|
||||
|
|
|
@ -20,6 +20,8 @@ enum printk_info_flags {
|
|||
LOG_CONT = 8, /* text is a fragment of a continuation line */
|
||||
};
|
||||
|
||||
extern bool block_console_kthreads;
|
||||
|
||||
__printf(4, 0)
|
||||
int vprintk_store(int facility, int level,
|
||||
const struct dev_printk_info *dev_info,
|
||||
|
|
|
@ -250,6 +250,9 @@ static atomic_t console_kthreads_active = ATOMIC_INIT(0);
|
|||
#define console_kthread_printing_exit() \
|
||||
atomic_dec(&console_kthreads_active)
|
||||
|
||||
/* Block console kthreads to avoid processing new messages. */
|
||||
bool block_console_kthreads;
|
||||
|
||||
/*
|
||||
* Helper macros to handle lockdep when locking/unlocking console_sem. We use
|
||||
* macros instead of functions so that _RET_IP_ contains useful information.
|
||||
|
@ -3729,7 +3732,10 @@ static bool printer_should_wake(struct console *con, u64 seq)
|
|||
return true;
|
||||
|
||||
if (con->blocked ||
|
||||
console_kthreads_atomically_blocked()) {
|
||||
console_kthreads_atomically_blocked() ||
|
||||
block_console_kthreads ||
|
||||
system_state > SYSTEM_RUNNING ||
|
||||
oops_in_progress) {
|
||||
return false;
|
||||
}
|
||||
|
||||
|
|
|
@ -8,7 +8,9 @@
|
|||
#include <linux/smp.h>
|
||||
#include <linux/cpumask.h>
|
||||
#include <linux/printk.h>
|
||||
#include <linux/console.h>
|
||||
#include <linux/kprobes.h>
|
||||
#include <linux/delay.h>
|
||||
|
||||
#include "internal.h"
|
||||
|
||||
|
@ -50,3 +52,33 @@ asmlinkage int vprintk(const char *fmt, va_list args)
|
|||
return vprintk_default(fmt, args);
|
||||
}
|
||||
EXPORT_SYMBOL(vprintk);
|
||||
|
||||
/**
|
||||
* try_block_console_kthreads() - Try to block console kthreads and
|
||||
* make the global console_lock() avaialble
|
||||
*
|
||||
* @timeout_ms: The maximum time (in ms) to wait.
|
||||
*
|
||||
* Prevent console kthreads from starting processing new messages. Wait
|
||||
* until the global console_lock() become available.
|
||||
*
|
||||
* Context: Can be called in any context.
|
||||
*/
|
||||
void try_block_console_kthreads(int timeout_ms)
|
||||
{
|
||||
block_console_kthreads = true;
|
||||
|
||||
/* Do not wait when the console lock could not be safely taken. */
|
||||
if (this_cpu_read(printk_context) || in_nmi())
|
||||
return;
|
||||
|
||||
while (timeout_ms > 0) {
|
||||
if (console_trylock()) {
|
||||
console_unlock();
|
||||
return;
|
||||
}
|
||||
|
||||
udelay(1000);
|
||||
timeout_ms -= 1;
|
||||
}
|
||||
}
|
||||
|
|
|
@ -82,6 +82,7 @@ void kernel_restart_prepare(char *cmd)
|
|||
{
|
||||
blocking_notifier_call_chain(&reboot_notifier_list, SYS_RESTART, cmd);
|
||||
system_state = SYSTEM_RESTART;
|
||||
try_block_console_kthreads(10000);
|
||||
usermodehelper_disable();
|
||||
device_shutdown();
|
||||
}
|
||||
|
@ -270,6 +271,7 @@ static void kernel_shutdown_prepare(enum system_states state)
|
|||
blocking_notifier_call_chain(&reboot_notifier_list,
|
||||
(state == SYSTEM_HALT) ? SYS_HALT : SYS_POWER_OFF, NULL);
|
||||
system_state = state;
|
||||
try_block_console_kthreads(10000);
|
||||
usermodehelper_disable();
|
||||
device_shutdown();
|
||||
}
|
||||
|
|
Loading…
Reference in a new issue