The UEFI spec does not require interrupts to be disabled when invoking runtime services. The reason we have been doing so is because EFI pstore may call SetVariable() from interrupt context, which may result in deadlock if another runtime services call was in progress on the same cpu. The EFI pstore has already been updated to use a non-blocking path and fail gracefully rather than spin forever, so we can updated the ordinary blocking wrappers to run with interrupts enabled instead. This aims to prevent excessive interrupt latencies on uniprocessor platforms with slow variable stores. Changes since v2: - added nonblocking QueryVariableInfo() wrapper variant, and updated efi_query_variable_store() to use it when called in nonblocking context - add patch to drop the rtc_lock spinlock - add patch to drop redundant efi_set_variable_nonblocking_t typedef - drop BUG_ONs in patch #7 Ard Biesheuvel (7): efi: expose non-blocking set_variable() wrapper to efivars efi: remove redundant efi_set_variable_nonblocking prototype efi: runtime-wrappers: add a nonblocking version of QueryVariableInfo efi: add nonblocking option to efi_query_variable_store() efi: runtime-wrappers: remove out of date comment regarding in_nmi() efi: runtime-wrapper: get rid of the rtc_lock spinlock efi: runtime-wrappers: run UEFI Runtime Services with interrupts enabled arch/x86/platform/efi/quirks.c | 37 +++++-- drivers/firmware/efi/efi.c | 1 + drivers/firmware/efi/runtime-wrappers.c | 115 +++++++------------- drivers/firmware/efi/vars.c | 16 ++- include/linux/efi.h | 21 ++-- 5 files changed, 94 insertions(+), 96 deletions(-) -- 1.9.1 -- To unsubscribe from this list: send the line "unsubscribe linux-efi" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html