On 4/15/20 11:55 AM, Steven Rostedt wrote: > On Tue, Apr 14, 2020 at 12:26:29PM -0700, Brendan Higgins wrote: >> On Sat, Apr 11, 2020 at 11:22 PM Randy Dunlap <rdunlap@xxxxxxxxxxxxx> wrote: >>> >>> On 4/11/20 10:36 PM, Naresh Kamboju wrote: >>>> FYI, >>>> >>>> Is this problem related to, >>>> >>>> Regression reported on Linux next 5.6.0-rc4-next-20200305 on x86_64, >>>> i386, arm and arm64. The steps to reproduce is running kselftests lib >>>> printf.sh test case. >>>> Which is doing modprobe operations. >>>> >>>> BUG: kernel NULL pointer dereference, address: 00 - ida_free+0x76/0x140 >>>> >>>> https://lore.kernel.org/linux-kselftest/CAFd5g46Bwd8HS9-xjHLh_rB59Nfw8iAnM6aFe0QPcveewDUT6g@xxxxxxxxxxxxxx/T/ >>>> >>> >>> Looks similar. Lots of fwnode, software_node, ida stuff there. >> >> Sorry for the late reply, I was out. >> >> Yeah, I am pretty sure it is the same. Heikki proposed a fix that I am >> going to try. > > My test suite just tripped over this bug. Is this the patch that you think > fixes it? > > https://lore.kernel.org/linux-kselftest/20200414081513.GD2828150@xxxxxxxxxxxxxxxxx Yes, it is, but GregKH and Rafael Wysocki don't seem to like that patch and are suggesting some changes in lib/kobject.c (only pseudocode, no patch yet). > I'll add it to see if I can continue my testing. See the thread [PATCH v1] kobject: make sure parent is not released before children Here is Rafael's suggestion: https://lore.kernel.org/linux-kselftest/CAJZ5v0hNemTDVa_S-FfVMbrKjM-RWYoHh88asnUvTNxZinY2cw@xxxxxxxxxxxxxx/ -- ~Randy
