From: Vasant Hegde hegdevasant@linux.vnet.ibm.com
commit 52862ab33c5d97490f3fa345d6529829e6d6637b upstream.
Commit 587164cd, introduced new opal message type (OPAL_MSG_PRD2) and added opal notifier. But I missed to unregister the notifier during module unload path. This results in below call trace if you try to unload and load opal_prd module.
Also add new notifier_block for OPAL_MSG_PRD2 message.
Sample calltrace (modprobe -r opal_prd; modprobe opal_prd) BUG: Unable to handle kernel data access on read at 0xc0080000192200e0 Faulting instruction address: 0xc00000000018d1cc Oops: Kernel access of bad area, sig: 11 [#1] LE PAGE_SIZE=64K MMU=Radix SMP NR_CPUS=2048 NUMA PowerNV CPU: 66 PID: 7446 Comm: modprobe Kdump: loaded Tainted: G E 5.14.0prd #759 NIP: c00000000018d1cc LR: c00000000018d2a8 CTR: c0000000000cde10 REGS: c0000003c4c0f0a0 TRAP: 0300 Tainted: G E (5.14.0prd) MSR: 9000000002009033 <SF,HV,VEC,EE,ME,IR,DR,RI,LE> CR: 24224824 XER: 20040000 CFAR: c00000000018d2a4 DAR: c0080000192200e0 DSISR: 40000000 IRQMASK: 1 ... NIP notifier_chain_register+0x2c/0xc0 LR atomic_notifier_chain_register+0x48/0x80 Call Trace: 0xc000000002090610 (unreliable) atomic_notifier_chain_register+0x58/0x80 opal_message_notifier_register+0x7c/0x1e0 opal_prd_probe+0x84/0x150 [opal_prd] platform_probe+0x78/0x130 really_probe+0x110/0x5d0 __driver_probe_device+0x17c/0x230 driver_probe_device+0x60/0x130 __driver_attach+0xfc/0x220 bus_for_each_dev+0xa8/0x130 driver_attach+0x34/0x50 bus_add_driver+0x1b0/0x300 driver_register+0x98/0x1a0 __platform_driver_register+0x38/0x50 opal_prd_driver_init+0x34/0x50 [opal_prd] do_one_initcall+0x60/0x2d0 do_init_module+0x7c/0x320 load_module+0x3394/0x3650 __do_sys_finit_module+0xd4/0x160 system_call_exception+0x140/0x290 system_call_common+0xf4/0x258
Fixes: 587164cd593c ("powerpc/powernv: Add new opal message type") Cc: stable@vger.kernel.org # v5.4+ Signed-off-by: Vasant Hegde hegdevasant@linux.vnet.ibm.com Signed-off-by: Michael Ellerman mpe@ellerman.id.au Link: https://lore.kernel.org/r/20211028165716.41300-1-hegdevasant@linux.vnet.ibm.... Signed-off-by: Greg Kroah-Hartman gregkh@linuxfoundation.org --- arch/powerpc/platforms/powernv/opal-prd.c | 12 +++++++++++- 1 file changed, 11 insertions(+), 1 deletion(-)
--- a/arch/powerpc/platforms/powernv/opal-prd.c +++ b/arch/powerpc/platforms/powernv/opal-prd.c @@ -369,6 +369,12 @@ static struct notifier_block opal_prd_ev .priority = 0, };
+static struct notifier_block opal_prd_event_nb2 = { + .notifier_call = opal_prd_msg_notifier, + .next = NULL, + .priority = 0, +}; + static int opal_prd_probe(struct platform_device *pdev) { int rc; @@ -390,9 +396,10 @@ static int opal_prd_probe(struct platfor return rc; }
- rc = opal_message_notifier_register(OPAL_MSG_PRD2, &opal_prd_event_nb); + rc = opal_message_notifier_register(OPAL_MSG_PRD2, &opal_prd_event_nb2); if (rc) { pr_err("Couldn't register PRD2 event notifier\n"); + opal_message_notifier_unregister(OPAL_MSG_PRD, &opal_prd_event_nb); return rc; }
@@ -401,6 +408,8 @@ static int opal_prd_probe(struct platfor pr_err("failed to register miscdev\n"); opal_message_notifier_unregister(OPAL_MSG_PRD, &opal_prd_event_nb); + opal_message_notifier_unregister(OPAL_MSG_PRD2, + &opal_prd_event_nb2); return rc; }
@@ -411,6 +420,7 @@ static int opal_prd_remove(struct platfo { misc_deregister(&opal_prd_dev); opal_message_notifier_unregister(OPAL_MSG_PRD, &opal_prd_event_nb); + opal_message_notifier_unregister(OPAL_MSG_PRD2, &opal_prd_event_nb2); return 0; }