Johannes Berg 68025adfc1 um: fix _nofault accesses ... Nathan reported [1] that when built with clang, the um kernel crashes pretty much immediately. This turned out to be an issue with the inline assembly I had added, when clang used %rax/%eax for both operands. Reorder it so current->thread.segv_continue is written first, and then the lifetime of _faulted won't have overlap with the lifetime of segv_continue. In the email thread Benjamin also pointed out that current->mm is only NULL for true kernel tasks, but we could do this for a userspace task, so the current->thread.segv_continue logic must be lifted out of the mm==NULL check. Finally, while looking at this, put a barrier() so the NULL assignment to thread.segv_continue cannot be reorder before the possibly faulting operation. Reported-by: Nathan Chancellor <nathan@kernel.org> Closes: https://lore.kernel.org/r/20250402221254.GA384@ax162 [1] Fixes: d1d7f01f7c ("um: mark rodata read-only and implement _nofault accesses") Tested-by: Nathan Chancellor <nathan@kernel.org> Signed-off-by: Johannes Berg <johannes.berg@intel.com>		2025-05-05 10:06:51 +02:00
..
asm	um: fix _nofault accesses	2025-05-05 10:06:51 +02:00
linux	um: work around sched_yield not yielding in time-travel mode	2025-03-18 11:06:20 +01:00
shared	Updates for UML for this cycle, notably:	2025-04-02 12:25:03 -07:00
uapi/asm	um: Fix W=1 missing-include-dirs warnings	2021-04-15 23:10:57 +02:00