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| author | Anton Ivanov <anton.ivanov@cambridgegreys.com> | 2024-07-02 10:25:50 +0200 |
|---|---|---|
| committer | Johannes Berg <johannes.berg@intel.com> | 2024-07-03 17:10:43 +0200 |
| commit | cd01672d64a358cccc087c8b845ebe6b7e9e2ca4 (patch) | |
| tree | ba65019fb557e0422ff581ed802e2c75467a686f /arch/um | |
| parent | bcf3d957c63d8b6d718b862fea18c5f14ce803e2 (diff) | |
um: Enable preemption in UML
Since userspace state is saved in the MM process, kernel using
FPU still doesn't really need to do anything, so this really
is as simple as enabling preemption. The irq critical section
in sigio_handler() needs preempt_disable()/preempt_enable().
Signed-off-by: Anton Ivanov <anton.ivanov@cambridgegreys.com>
Link: https://patch.msgid.link/20240702102549.d2fcea450854.I12f5a53d80ec1e425e66ef272b1e95cb523b608e@changeid
[rebase, remove FPU save/restore, fix x86/um Makefile,
rewrite commit message]
Signed-off-by: Johannes Berg <johannes.berg@intel.com>
Diffstat (limited to 'arch/um')
| -rw-r--r-- | arch/um/Kconfig | 2 | ||||
| -rw-r--r-- | arch/um/kernel/irq.c | 2 |
2 files changed, 3 insertions, 1 deletions
diff --git a/arch/um/Kconfig b/arch/um/Kconfig index 1faefc0a18ea..dca84fd6d00a 100644 --- a/arch/um/Kconfig +++ b/arch/um/Kconfig @@ -11,7 +11,7 @@ config UML select ARCH_HAS_KCOV select ARCH_HAS_STRNCPY_FROM_USER select ARCH_HAS_STRNLEN_USER - select ARCH_NO_PREEMPT + select ARCH_NO_PREEMPT_DYNAMIC select HAVE_ARCH_AUDITSYSCALL select HAVE_ARCH_KASAN if X86_64 select HAVE_ARCH_KASAN_VMALLOC if HAVE_ARCH_KASAN diff --git a/arch/um/kernel/irq.c b/arch/um/kernel/irq.c index ceda4bd2e5ed..534e91797f89 100644 --- a/arch/um/kernel/irq.c +++ b/arch/um/kernel/irq.c @@ -238,7 +238,9 @@ static void _sigio_handler(struct uml_pt_regs *regs, void sigio_handler(int sig, struct siginfo *unused_si, struct uml_pt_regs *regs) { + preempt_disable(); _sigio_handler(regs, irqs_suspended); + preempt_enable(); } static struct irq_entry *get_irq_entry_by_fd(int fd) |