Re: [PATCH] Revert "i2c: dev: switch from register_chrdev to cdev API"

2016-05-30 Thread Dan Carpenter
On Sat, May 28, 2016 at 06:04:58PM +0200, Wolfram Sang wrote: > > > These kinds of use after frees don't always cause a runtime problem. I > > found it using static analysis, but I bet you could detect it if you > > enabled kasan. The other option is to enable PAGE_POISONING? > > Thanks,

Re: [PATCH] Revert "i2c: dev: switch from register_chrdev to cdev API"

2016-05-30 Thread Dan Carpenter
On Sat, May 28, 2016 at 06:04:58PM +0200, Wolfram Sang wrote: > > > These kinds of use after frees don't always cause a runtime problem. I > > found it using static analysis, but I bet you could detect it if you > > enabled kasan. The other option is to enable PAGE_POISONING? > > Thanks,

Re: [PATCH] Revert "i2c: dev: switch from register_chrdev to cdev API"

2016-05-28 Thread Wolfram Sang
> These kinds of use after frees don't always cause a runtime problem. I > found it using static analysis, but I bet you could detect it if you > enabled kasan. The other option is to enable PAGE_POISONING? Thanks, PAGE_POISONING did trigger the issue. So, I now picked up your patch instead of

Re: [PATCH] Revert "i2c: dev: switch from register_chrdev to cdev API"

2016-05-28 Thread Wolfram Sang
> These kinds of use after frees don't always cause a runtime problem. I > found it using static analysis, but I bet you could detect it if you > enabled kasan. The other option is to enable PAGE_POISONING? Thanks, PAGE_POISONING did trigger the issue. So, I now picked up your patch instead of

Re: [PATCH] Revert "i2c: dev: switch from register_chrdev to cdev API"

2016-05-28 Thread Dan Carpenter
On Sat, May 28, 2016 at 11:07:47AM +0200, Wolfram Sang wrote: > This reverts commit d6760b14d4a1243f918d983bba1e35c5a5cd5a6d. When > hitting Linus' tree, buildbots ran additional checks and found boot > problems. Although Dan Carpenter provided an obvious fix already, I > still could not reproduce

Re: [PATCH] Revert "i2c: dev: switch from register_chrdev to cdev API"

2016-05-28 Thread Dan Carpenter
On Sat, May 28, 2016 at 11:07:47AM +0200, Wolfram Sang wrote: > This reverts commit d6760b14d4a1243f918d983bba1e35c5a5cd5a6d. When > hitting Linus' tree, buildbots ran additional checks and found boot > problems. Although Dan Carpenter provided an obvious fix already, I > still could not reproduce

[PATCH] Revert "i2c: dev: switch from register_chrdev to cdev API"

2016-05-28 Thread Wolfram Sang
This reverts commit d6760b14d4a1243f918d983bba1e35c5a5cd5a6d. When hitting Linus' tree, buildbots ran additional checks and found boot problems. Although Dan Carpenter provided an obvious fix already, I still could not reproduce one problem manually (at least not on a Saturday morning). So we'll

[PATCH] Revert "i2c: dev: switch from register_chrdev to cdev API"

2016-05-28 Thread Wolfram Sang
This reverts commit d6760b14d4a1243f918d983bba1e35c5a5cd5a6d. When hitting Linus' tree, buildbots ran additional checks and found boot problems. Although Dan Carpenter provided an obvious fix already, I still could not reproduce one problem manually (at least not on a Saturday morning). So we'll