mirror of
https://mirrors.bfsu.edu.cn/git/linux.git
synced 2024-11-15 08:14:15 +08:00
4c45c5167c
When a panic happens during bootup, "Rebooting in X seconds.." is shown, but reboot happens immediatelly. It is because panic() uses mdelay() and mdelay() calls __const_udelay() immediately, which does not work while booting. The per_cpu cpu_info.loops_per_jiffy value is not initialized yet, so __const_udelay() actually multiplies the number of loops by zero. This results in __const_udelay() to delay the execution only by a nanosecond or so. So check whether cpu_info.loops_per_jiffy is zero and use loops_per_jiffy in that case. mdelay() will not be so precise without proper calibration, but it works relatively well. Before: [ 0.170039] delaying 100ms [ 0.170828] done After [ 0.214042] delaying 100ms [ 0.313974] done I do not think the added check matters given we are about to spin the processor in the next few hundred cycles. Signed-off-by: Jiri Slaby <jslaby@suse.cz> Reviewed-by: Andy Shevchenko <andy.shevchenko@gmail.com> Acked-by: Thomas Gleixner <tglx@linutronix.de> Cc: Linus Torvalds <torvalds@linux-foundation.org> Cc: Peter Zijlstra <peterz@infradead.org> Link: http://lkml.kernel.org/r/20170119114730.2670-1-jslaby@suse.cz [ Minor edits. ] Signed-off-by: Ingo Molnar <mingo@kernel.org> |
||
|---|---|---|
| .. | ||
| alpha | ||
| arc | ||
| arm | ||
| arm64 | ||
| avr32 | ||
| blackfin | ||
| c6x | ||
| cris | ||
| frv | ||
| h8300 | ||
| hexagon | ||
| ia64 | ||
| m32r | ||
| m68k | ||
| metag | ||
| microblaze | ||
| mips | ||
| mn10300 | ||
| nios2 | ||
| openrisc | ||
| parisc | ||
| powerpc | ||
| s390 | ||
| score | ||
| sh | ||
| sparc | ||
| tile | ||
| um | ||
| unicore32 | ||
| x86 | ||
| xtensa | ||
| .gitignore | ||
| Kconfig | ||