On Sat, Oct 12, 2024 at 4:31 PM Bjorn Helgaas <helgaas@xxxxxxxxxx> wrote: > > On Thu, Oct 10, 2024 at 11:17:47AM +0200, Bartosz Golaszewski wrote: > > On Thu, Oct 3, 2024 at 10:43 AM Bartosz Golaszewski <brgl@xxxxxxxx> wrote: > > > > > > From: Bartosz Golaszewski <bartosz.golaszewski@xxxxxxxxxx> > > > > > > Since adding the PCI power control code, we may end up with a race > > > between the pwrctl platform device rescanning the bus and the host > > > controller probe function. The latter needs to take the rescan lock when > > > adding devices or we may end up in an undefined state having two > > > incompletely added devices and hit the following crash when trying to > > > remove the device over sysfs: > > > > > > Unable to handle kernel NULL pointer dereference at virtual address 0000000000000000 > > > Internal error: Oops: 0000000096000004 [#1] SMP > > > Call trace: > > > __pi_strlen+0x14/0x150 > > > kernfs_find_ns+0x80/0x13c > > > kernfs_remove_by_name_ns+0x54/0xf0 > > > sysfs_remove_bin_file+0x24/0x34 > > > pci_remove_resource_files+0x3c/0x84 > > > pci_remove_sysfs_dev_files+0x28/0x38 > > > pci_stop_bus_device+0x8c/0xd8 > > > pci_stop_bus_device+0x40/0xd8 > > > pci_stop_and_remove_bus_device_locked+0x28/0x48 > > > remove_store+0x70/0xb0 > > > dev_attr_store+0x20/0x38 > > > sysfs_kf_write+0x58/0x78 > > > kernfs_fop_write_iter+0xe8/0x184 > > > vfs_write+0x2dc/0x308 > > > ksys_write+0x7c/0xec > > > > > > Reported-by: Konrad Dybcio <konradybcio@xxxxxxxxxx> > > > Tested-by: Konrad Dybcio <konradybcio@xxxxxxxxxx> > > > Fixes: 4565d2652a37 ("PCI/pwrctl: Add PCI power control core code") > > > Signed-off-by: Bartosz Golaszewski <bartosz.golaszewski@xxxxxxxxxx> > > > --- > > > > It's been a week, so gentle ping - can this be picked up into v6.12? > > I hoped we could fix the similar latent issues in other drivers, but > yes, we can get this in v6.12. Thanks for the hint that it should go > there. I'll pick it up when I return from vacation on Wednesday. > Sure this can still be done but this patch fixes an urgent issue and I think it warrants fast tracking it to mainline. Bart