Hi all,
Any idea on this regression?
Thanks,
Joseph
On 19/6/5 18:23, Joseph Qi wrote:
> Hi,
>
> I have encountered a kernel BUG when running ltp ftrace-stress-test
> on 4.19.48.
>
> [ 209.704855] LTP: starting ftrace-stress-test (ftrace_stress_test.sh 90)
> [ 209.739412] Scheduler tracepoints stat_sleep, stat_iowait, stat_blocked
> and stat_runtime require the kernel parameter schedstats=enable or
> kernel.sched_schedstats=1
> [ 212.054506] kernel tried to execute NX-protected page - exploit attempt?
> (uid: 0)
> [ 212.055595] BUG: unable to handle kernel paging request at ffffffffc0349000
> [ 212.056589] PGD d00c067 P4D d00c067 PUD d00e067 PMD 23673e067 PTE
> 800000023457f061
> [ 212.057759] Oops: 0011 [#1] SMP PTI
> [ 212.058303] CPU: 0 PID: 0 Comm: swapper/0 Kdump: loaded Not tainted
> 4.19.48 #112
>
> After some investigation I have found that it is introduced by commit
> 8715ce033eb3 ("x86/modules: Avoid breaking W^X while loading modules"),
> and then revert this commit the issue is gone.
>
> I have also tested the same case on 5.2-rc3 as well as right at
> upstream commit f2c65fb3221a ("x86/modules: Avoid breaking W^X while
> loading modules"), which has been merged in 5.2-rc1, it doesn't
> happen.
>
> So I don't know why only stable has this issue while upstream doesn't.
>
> Thanks,
> Joseph
>
