Messages in this thread | | | From | Sergey Senozhatsky <> | Date | Tue, 19 Mar 2019 21:35:00 +0900 | Subject | Re: [syzbot? printk?] no WARN_ON() messages printed before "Kernel panic - not syncing: panic_on_warn set ..." |
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On (03/19/19 09:10), Dmitry Vyukov wrote:
[..]
> In some setups we read out output with "dmesg -w" (should stream > output as well) in absence of a better solution. Will this be affected > by SYSLOG_ACTION_CLEAR?
There is a small chance that syslog/devkmsg can be affected
syslog_clear() { clear_seq = log_next_seq; clear_idx = log_next_idx; }
syslog_print_all() { ... seq = clear_seq; idx = clear_idx; while (seq < log_next_seq) { ... len += msg_print_text(msg, true, time, NULL, 0); } ... }
devkmsg also may be affected
syslog_clear() { clear_seq = log_next_seq; clear_idx = log_next_idx; }
devkmsg_llseek() { ... case SEEK_DATA: user->idx = clear_idx; user->seq = clear_seq; break; ... }
user->idx/user->seq then are used in devkmsg poll()/read(). syslog is more likely to be affected, I think.
-ss
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