4.4-stable review patch. If anyone has any objections, please let me know.
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This reverts commit 7212e37cbdf99f48e4a6c689a42f4bda1ae69001.
Hedi Berriche hedi.berriche@hpe.com notes:
In 4.4-stable efi_runtime_lock as defined in drivers/firmware/efi/runtime-wrappers.c is a spinlock (given it predates commit dce48e351c0d) and commit
f331e766c4be x86/platform/UV: Use efi_runtime_lock to serialise BIOS callswhich 7212e37cbdf9 is a backport of, needs it to be a semaphore.
Signed-off-by: Sasha Levin sashal@kernel.org --- arch/x86/include/asm/uv/bios.h | 8 +------- arch/x86/platform/uv/bios_uv.c | 23 ++--------------------- drivers/firmware/efi/runtime-wrappers.c | 7 ------- 3 files changed, 3 insertions(+), 35 deletions(-)
--- a/arch/x86/include/asm/uv/bios.h +++ b/arch/x86/include/asm/uv/bios.h @@ -48,8 +48,7 @@ enum { BIOS_STATUS_SUCCESS = 0, BIOS_STATUS_UNIMPLEMENTED = -ENOSYS, BIOS_STATUS_EINVAL = -EINVAL, - BIOS_STATUS_UNAVAIL = -EBUSY, - BIOS_STATUS_ABORT = -EINTR, + BIOS_STATUS_UNAVAIL = -EBUSY };
/* @@ -112,9 +111,4 @@ extern long system_serial_number;
extern struct kobject *sgi_uv_kobj; /* /sys/firmware/sgi_uv */
-/* - * EFI runtime lock; cf. firmware/efi/runtime-wrappers.c for details - */ -extern struct semaphore __efi_uv_runtime_lock; - #endif /* _ASM_X86_UV_BIOS_H */ --- a/arch/x86/platform/uv/bios_uv.c +++ b/arch/x86/platform/uv/bios_uv.c @@ -28,8 +28,7 @@
static struct uv_systab uv_systab;
-static s64 __uv_bios_call(enum uv_bios_cmd which, u64 a1, u64 a2, u64 a3, - u64 a4, u64 a5) +s64 uv_bios_call(enum uv_bios_cmd which, u64 a1, u64 a2, u64 a3, u64 a4, u64 a5) { struct uv_systab *tab = &uv_systab; s64 ret; @@ -44,19 +43,6 @@ static s64 __uv_bios_call(enum uv_bios_c a1, a2, a3, a4, a5); return ret; } - -s64 uv_bios_call(enum uv_bios_cmd which, u64 a1, u64 a2, u64 a3, u64 a4, u64 a5) -{ - s64 ret; - - if (down_interruptible(&__efi_uv_runtime_lock)) - return BIOS_STATUS_ABORT; - - ret = __uv_bios_call(which, a1, a2, a3, a4, a5); - up(&__efi_uv_runtime_lock); - - return ret; -} EXPORT_SYMBOL_GPL(uv_bios_call);
s64 uv_bios_call_irqsave(enum uv_bios_cmd which, u64 a1, u64 a2, u64 a3, @@ -65,15 +51,10 @@ s64 uv_bios_call_irqsave(enum uv_bios_cm unsigned long bios_flags; s64 ret;
- if (down_interruptible(&__efi_uv_runtime_lock)) - return BIOS_STATUS_ABORT; - local_irq_save(bios_flags); - ret = __uv_bios_call(which, a1, a2, a3, a4, a5); + ret = uv_bios_call(which, a1, a2, a3, a4, a5); local_irq_restore(bios_flags);
- up(&__efi_uv_runtime_lock); - return ret; }
--- a/drivers/firmware/efi/runtime-wrappers.c +++ b/drivers/firmware/efi/runtime-wrappers.c @@ -88,13 +88,6 @@ static DEFINE_SPINLOCK(efi_runtime_lock) */
/* - * Expose the EFI runtime lock to the UV platform - */ -#ifdef CONFIG_X86_UV -extern struct semaphore __efi_uv_runtime_lock __alias(efi_runtime_lock); -#endif - -/* * As per commit ef68c8f87ed1 ("x86: Serialize EFI time accesses on rtc_lock"), * the EFI specification requires that callers of the time related runtime * functions serialize with other CMOS accesses in the kernel, as the EFI time