On 9/4/2019 6:55 PM, Trond Myklebust wrote: > On Tue, 2019-04-09 at 18:25 +0200, Daniel Mack wrote: >> On 8/4/2019 8:51 PM, Trond Myklebust wrote: >>> On Mon, 2019-04-08 at 19:01 +0200, Daniel Mack wrote: >>>> Hi, >>>> >>>> I'm seeing the Oops below when trying to boot 5.1.0-rc4 on an ARM >>>> PXA3xx >>>> platform. v5.0 did not show this effect with the same cmdline. >>>> >>> Please do bisect if that is at all practical. I'm having trouble >>> interpreting this Oops. >> >> Here you go: >> >> 009a82f6437490c262584d65a14094a818bcb747 is the first bad commit >> commit 009a82f6437490c262584d65a14094a818bcb747 >> Author: Trond Myklebust <trond.myklebust@xxxxxxxxxxxxxxx> >> Date: Sat Mar 9 12:07:17 2019 -0500 >> >> SUNRPC: Micro-optimise when the task is known not to be sleeping >> >> In cases where we know the task is not sleeping, try to optimise >> away the indirect call to task->tk_action() by replacing it with >> a direct call. >> Only change tail calls, to allow gcc to perform tail call >> elimination. > > Ah... It looks like we explicitly turn off tail call optimisation in > some ARM configs, so this might be a stack overflow. > > Does your config file have THUMB2_AVOID_R_ARM_THM_JUMP11 set? Nope. I don't even have THUMB2_KERNEL. In the meantime, I tried to trace that with some printks, but the bug appears evasive, and the backtrace changes as soon as I modify the timing. Hmm. Happy to test patches if you have any idea. Thanks, Daniel
