Hi Sudeep, fixes the crash for me.
Tested-by: Cristian Marussi <[email protected]> Reviewed-by: Cristian Marussi <[email protected]> Thanks Cristian On Mon, Nov 30, 2020 at 10:28:04AM +0000, Sudeep Holla wrote: > The mhu_db_channel info is allocated per channel using devm_kzalloc from > mhu_db_mbox_xlate which gets called from mbox_request_channel. However > we are releasing the allocated mhu_db_channel info using plain kfree from > mhu_db_shutdown which is called from mbox_free_channel. > > This leads to random crashes when the channel is freed like below one: > > Unable to handle kernel paging request at virtual address 0080000400000008 > [0080000400000008] address between user and kernel address ranges > Internal error: Oops: 96000044 [#1] PREEMPT SMP > Modules linked in: scmi_module(-) > CPU: 1 PID: 2212 Comm: rmmod Not tainted 5.10.0-rc5 #31 > Hardware name: ARM LTD ARM Juno Development Platform/ARM Juno > Development Platform, BIOS EDK II Nov 19 2020 > pstate: 20000085 (nzCv daIf -PAN -UAO -TCO BTYPE=--) > pc : release_nodes+0x74/0x230 > lr : devres_release_all+0x40/0x68 > Call trace: > release_nodes+0x74/0x230 > devres_release_all+0x40/0x68 > device_release_driver_internal+0x12c/0x1f8 > driver_detach+0x58/0xe8 > bus_remove_driver+0x64/0xe0 > driver_unregister+0x38/0x68 > platform_driver_unregister+0x1c/0x28 > scmi_driver_exit+0x38/0x44 [scmi_module] > __arm64_sys_delete_module+0x188/0x260 > el0_svc_common.constprop.0+0x80/0x1a8 > do_el0_svc+0x2c/0x98 > el0_sync_handler+0x160/0x168 > el0_sync+0x174/0x180 > Code: 1400000d eb07009f 54000460 f9400486 (f90004a6) > ---[ end trace c55ffd306c140233 ]--- > > Fix it by replacing kfree with devm_kfree as required. > > Fixes: 7002ca237b21 ("mailbox: arm_mhu: Add ARM MHU doorbell driver") > Reported-by: Cristian Marussi <[email protected]> > Signed-off-by: Sudeep Holla <[email protected]> > --- > drivers/mailbox/arm_mhu_db.c | 2 +- > 1 file changed, 1 insertion(+), 1 deletion(-) > > diff --git a/drivers/mailbox/arm_mhu_db.c b/drivers/mailbox/arm_mhu_db.c > index 275efe4cca0c..8eb66c4ecf5b 100644 > --- a/drivers/mailbox/arm_mhu_db.c > +++ b/drivers/mailbox/arm_mhu_db.c > @@ -180,7 +180,7 @@ static void mhu_db_shutdown(struct mbox_chan *chan) > > /* Reset channel */ > mhu_db_mbox_clear_irq(chan); > - kfree(chan->con_priv); > + devm_kfree(mbox->dev, chan->con_priv); > chan->con_priv = NULL; > } > > -- > 2.25.1 >
