Re: limits->max_sectors is getting set to 0, why/where? [was: Re: dm: kernel oops by divide error on v4.16+]

2018-04-09 Thread Jens Axboe
On 4/9/18 5:54 PM, Linus Torvalds wrote: > On Mon, Apr 9, 2018 at 3:32 PM, Jens Axboe wrote: >> >> The resulting min/max and friends would have been trivial to test, but >> clearly they weren't. > > Well, the min/max macros themselves actually were tested in user space by me. > > It was the inte

Re: limits->max_sectors is getting set to 0, why/where? [was: Re: dm: kernel oops by divide error on v4.16+]

2018-04-09 Thread Linus Torvalds
On Mon, Apr 9, 2018 at 3:32 PM, Jens Axboe wrote: > > The resulting min/max and friends would have been trivial to test, but > clearly they weren't. Well, the min/max macros themselves actually were tested in user space by me. It was the interaction with the unrelated "min_not_zero()" that wasn'

Re: limits->max_sectors is getting set to 0, why/where? [was: Re: dm: kernel oops by divide error on v4.16+]

2018-04-09 Thread Jens Axboe
On 4/9/18 4:38 PM, Kees Cook wrote: > On Mon, Apr 9, 2018 at 3:32 PM, Jens Axboe wrote: >> That's bad, for sure, but my worry was bigger than an oops or crash, >> we could have had corruption due to this. >> >> The resulting min/max and friends would have been trivial to test, but >> clearly they

Re: limits->max_sectors is getting set to 0, why/where? [was: Re: dm: kernel oops by divide error on v4.16+]

2018-04-09 Thread Kees Cook
On Mon, Apr 9, 2018 at 3:32 PM, Jens Axboe wrote: > That's bad, for sure, but my worry was bigger than an oops or crash, > we could have had corruption due to this. > > The resulting min/max and friends would have been trivial to test, but > clearly they weren't. Yeah, that was bad luck and my fa

Re: limits->max_sectors is getting set to 0, why/where? [was: Re: dm: kernel oops by divide error on v4.16+]

2018-04-09 Thread Jens Axboe
On 4/9/18 4:27 PM, Ming Lei wrote: > On Mon, Apr 09, 2018 at 04:10:17PM -0600, Jens Axboe wrote: >> On 4/9/18 4:05 PM, Kees Cook wrote: >>> On Mon, Apr 9, 2018 at 2:56 PM, Jens Axboe wrote: On 4/9/18 3:26 PM, Jens Axboe wrote: > On 4/9/18 1:32 PM, Jens Axboe wrote: >> On 4/9/18 12:38

Re: limits->max_sectors is getting set to 0, why/where? [was: Re: dm: kernel oops by divide error on v4.16+]

2018-04-09 Thread Ming Lei
On Mon, Apr 09, 2018 at 04:10:17PM -0600, Jens Axboe wrote: > On 4/9/18 4:05 PM, Kees Cook wrote: > > On Mon, Apr 9, 2018 at 2:56 PM, Jens Axboe wrote: > >> On 4/9/18 3:26 PM, Jens Axboe wrote: > >>> On 4/9/18 1:32 PM, Jens Axboe wrote: > On 4/9/18 12:38 PM, Mike Snitzer wrote: > > On Mon

Re: limits->max_sectors is getting set to 0, why/where? [was: Re: dm: kernel oops by divide error on v4.16+]

2018-04-09 Thread Jens Axboe
On 4/9/18 4:05 PM, Kees Cook wrote: > On Mon, Apr 9, 2018 at 2:56 PM, Jens Axboe wrote: >> On 4/9/18 3:26 PM, Jens Axboe wrote: >>> On 4/9/18 1:32 PM, Jens Axboe wrote: On 4/9/18 12:38 PM, Mike Snitzer wrote: > On Mon, Apr 09 2018 at 11:51am -0400, > Mike Snitzer wrote: > >>

Re: limits->max_sectors is getting set to 0, why/where? [was: Re: dm: kernel oops by divide error on v4.16+]

2018-04-09 Thread Kees Cook
On Mon, Apr 9, 2018 at 2:56 PM, Jens Axboe wrote: > On 4/9/18 3:26 PM, Jens Axboe wrote: >> On 4/9/18 1:32 PM, Jens Axboe wrote: >>> On 4/9/18 12:38 PM, Mike Snitzer wrote: On Mon, Apr 09 2018 at 11:51am -0400, Mike Snitzer wrote: > On Sun, Apr 08 2018 at 12:00am -0400, > M

Re: limits->max_sectors is getting set to 0, why/where? [was: Re: dm: kernel oops by divide error on v4.16+]

2018-04-09 Thread Jens Axboe
On 4/9/18 3:26 PM, Jens Axboe wrote: > On 4/9/18 1:32 PM, Jens Axboe wrote: >> On 4/9/18 12:38 PM, Mike Snitzer wrote: >>> On Mon, Apr 09 2018 at 11:51am -0400, >>> Mike Snitzer wrote: >>> On Sun, Apr 08 2018 at 12:00am -0400, Ming Lei wrote: > Hi, > > The following ker

Re: limits->max_sectors is getting set to 0, why/where? [was: Re: dm: kernel oops by divide error on v4.16+]

2018-04-09 Thread Jens Axboe
On 4/9/18 1:32 PM, Jens Axboe wrote: > On 4/9/18 12:38 PM, Mike Snitzer wrote: >> On Mon, Apr 09 2018 at 11:51am -0400, >> Mike Snitzer wrote: >> >>> On Sun, Apr 08 2018 at 12:00am -0400, >>> Ming Lei wrote: >>> Hi, The following kernel oops(divide error) is triggered when running

Re: limits->max_sectors is getting set to 0, why/where? [was: Re: dm: kernel oops by divide error on v4.16+]

2018-04-09 Thread Jens Axboe
On 4/9/18 12:38 PM, Mike Snitzer wrote: > On Mon, Apr 09 2018 at 11:51am -0400, > Mike Snitzer wrote: > >> On Sun, Apr 08 2018 at 12:00am -0400, >> Ming Lei wrote: >> >>> Hi, >>> >>> The following kernel oops(divide error) is triggered when running >>> xfstest(generic/347) on ext4. >>> >>> [ 44

Re: limits->max_sectors is getting set to 0, why/where? [was: Re: dm: kernel oops by divide error on v4.16+]

2018-04-09 Thread Mike Snitzer
On Mon, Apr 09 2018 at 11:51am -0400, Mike Snitzer wrote: > On Sun, Apr 08 2018 at 12:00am -0400, > Ming Lei wrote: > > > Hi, > > > > The following kernel oops(divide error) is triggered when running > > xfstest(generic/347) on ext4. > > > > [ 442.632954] run fstests generic/347 at 2018-04-0