s390/topology: clear thread/group maps for offline cpus
The current code doesn't clear the thread/group maps for offline CPUs. This may cause kernel crashes like the one bewlow in common code that assumes if a CPU has sibblings it is online. Unable to handle kernel pointer dereference in virtual kernel address space Call Trace: [<000000013a4b8c3c>] blk_mq_map_swqueue+0x10c/0x388 ([<000000013a4b8bcc>] blk_mq_map_swqueue+0x9c/0x388) [<000000013a4b9300>] blk_mq_init_allocated_queue+0x448/0x478 [<000000013a4b9416>] blk_mq_init_queue+0x4e/0x90 [<000003ff8019d3e6>] loop_add+0x106/0x278 [loop] [<000003ff801b8148>] loop_init+0x148/0x1000 [loop] [<0000000139de4924>] do_one_initcall+0x3c/0x1e0 [<0000000139ef449a>] do_init_module+0x6a/0x2a0 [<0000000139ef61bc>] __do_sys_finit_module+0xa4/0xc0 [<0000000139de9e6e>] do_syscall+0x7e/0xd0 [<000000013a8e0aec>] __do_syscall+0xbc/0x110 [<000000013a8ee2e8>] system_call+0x78/0xa0 Fixes: 52aeda7a ("s390/topology: remove offline CPUs from CPU topology masks") Cc: <stable@kernel.org> # 5.7+ Reported-by:Marius Hillenbrand <mhillen@linux.ibm.com> Signed-off-by:
Sven Schnelle <svens@linux.ibm.com> Reviewed-by:
Heiko Carstens <hca@linux.ibm.com> Signed-off-by:
Vasily Gorbik <gor@linux.ibm.com>
parent
8c0795d2