linux-stable/arch/um/include
Johannes Berg 833f5208b1 um: defer killing userspace on page table update failures
commit a7d48886ca upstream.

In some cases we can get to fix_range_common() with mmap_sem held,
and in others we get there without it being held. For example, we
get there with it held from sys_mprotect(), and without it held
from fork_handler().

Avoid any issues in this and simply defer killing the task until
it runs the next time. Do it on the mm so that another task that
shares the same mm can't continue running afterwards.

Cc: stable@vger.kernel.org
Fixes: 468f65976a ("um: Fix hung task in fix_range_common()")
Signed-off-by: Johannes Berg <johannes.berg@intel.com>
Signed-off-by: Richard Weinberger <richard@nod.at>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2021-03-04 11:38:42 +01:00
..
asm um: Call pgtable_pmd_page_dtor() in __pmd_free_tlb() 2020-11-10 21:49:32 +01:00
linux um: Implement ndelay/udelay in time-travel mode 2020-03-29 23:29:52 +02:00
shared um: defer killing userspace on page table update failures 2021-03-04 11:38:42 +01:00