Am 03.02.20 um 10:06 schrieb Dan Carpenter:
On Sun, Feb 02, 2020 at 02:19:18PM +0100, Daniel Vetter wrote:
On Fri, Jan 31, 2020 at 11:28 PM syzbot syzbot+0dc4444774d419e916c8@syzkaller.appspotmail.com wrote:
Hello,
syzbot found the following crash on:
HEAD commit: 39bed42d Merge tag 'for-linus-hmm' of git://git.kernel.org.. git tree: upstream console output: https://nam11.safelinks.protection.outlook.com/?url=https%3A%2F%2Fsyzkaller.... kernel config: https://nam11.safelinks.protection.outlook.com/?url=https%3A%2F%2Fsyzkaller.... dashboard link: https://nam11.safelinks.protection.outlook.com/?url=https%3A%2F%2Fsyzkaller.... compiler: gcc (GCC) 9.0.0 20181231 (experimental) syz repro: https://nam11.safelinks.protection.outlook.com/?url=https%3A%2F%2Fsyzkaller....
The bug was bisected to:
commit 7611750784664db46d0db95631e322aeb263dde7 Author: Alex Deucher alexander.deucher@amd.com Date: Wed Jun 21 16:31:41 2017 +0000
drm/amdgpu: use kernel is_power_of_2 rather than local versionbisection log: https://nam11.safelinks.protection.outlook.com/?url=https%3A%2F%2Fsyzkaller.... final crash: https://nam11.safelinks.protection.outlook.com/?url=https%3A%2F%2Fsyzkaller.... console output: https://nam11.safelinks.protection.outlook.com/?url=https%3A%2F%2Fsyzkaller....
IMPORTANT: if you fix the bug, please add the following tag to the commit: Reported-by: syzbot+0dc4444774d419e916c8@syzkaller.appspotmail.com Fixes: 761175078466 ("drm/amdgpu: use kernel is_power_of_2 rather than local version")
Aside: This bisect line is complete nonsense ... I'm kinda at the point where I'm assuming that syzbot bisect results are garbage, which is maybe not what we want. I guess much stricter filtering for noise is needed, dunno. -Danile
With race conditions the git bisect is often nonsense.
Which makes sense, but we can still try to sanitize the result. I'm not familiar with the test case, but I think it doesn't even compile the amdgpu driver.
So skipping all patches of stuff you don't even compile would make not only the result of bisecting quite a bit more reliable, but also speed the process up quite a bit.
But no good idea to how teach that to a compile bot or the git bisect command.
Regards, Christian.
regards, dan carpenter