Re: [PATCH v4 1/5] arm64/entry: Unify user mode handling
André Almeida <[email protected]>
| Newsgroups | org.kernel.vger.linux-arch,org.infradead.lists.linux-arm-kernel,org.kernel.vger.linux-kernel |
|---|---|
| Message-ID | <[email protected]> |
Em 05/07/2026 14:56, André Almeida escreveu: > Currently, arm64 has two functions to prepare and handle context switches > from userspace: arm64_syscall_enter_from_user_mode() and > arm64_enter_from_user_mode(). The only difference is that the later calls > rseq_note_user_irq_entry() that sets rseq.event.user_irq as true. > > To ensure that futex_fixup_robust_unlock() works correctly, unify the > handling from user mode functions into one that always calls > rseq_note_user_irq_entry(). > > Other architectures calls irqentry_enter_from_user_mode() for syscalls > and interruptions, that sets rseq.event.user_irq as well. > > Signed-off-by: André Almeida <[email protected]> It turns out that this patch is not needed at all and futex_fixup_robust_unlock() is already working correctly for arm64. The user thread can't call a syscall in the middle of the vdso function.