From: Helge Deller deller@gmx.de
commit 157e9afcc4fa25068b0e8743bc254a9b56010e13 upstream.
This reverts commit 86d4d068df573a8c2105554624796c086d6bec3d.
Signed-off-by: Helge Deller deller@gmx.de Cc: stable@vger.kernel.org # v5.0+ Signed-off-by: Greg Kroah-Hartman gregkh@linuxfoundation.org
--- arch/parisc/include/asm/spinlock.h | 4 ++-- arch/parisc/kernel/syscall.S | 12 ++++-------- 2 files changed, 6 insertions(+), 10 deletions(-)
--- a/arch/parisc/include/asm/spinlock.h +++ b/arch/parisc/include/asm/spinlock.h @@ -37,8 +37,8 @@ static inline void arch_spin_unlock(arch volatile unsigned int *a;
a = __ldcw_align(x); - mb(); - *a = 1; + /* Release with ordered store. */ + __asm__ __volatile__("stw,ma %0,0(%1)" : : "r"(1), "r"(a) : "memory"); }
static inline int arch_spin_trylock(arch_spinlock_t *x) --- a/arch/parisc/kernel/syscall.S +++ b/arch/parisc/kernel/syscall.S @@ -640,8 +640,7 @@ cas_action: sub,<> %r28, %r25, %r0 2: stw %r24, 0(%r26) /* Free lock */ - sync - stw %r20, 0(%sr2,%r20) + stw,ma %r20, 0(%sr2,%r20) #if ENABLE_LWS_DEBUG /* Clear thread register indicator */ stw %r0, 4(%sr2,%r20) @@ -655,8 +654,7 @@ cas_action: 3: /* Error occurred on load or store */ /* Free lock */ - sync - stw %r20, 0(%sr2,%r20) + stw,ma %r20, 0(%sr2,%r20) #if ENABLE_LWS_DEBUG stw %r0, 4(%sr2,%r20) #endif @@ -857,8 +855,7 @@ cas2_action:
cas2_end: /* Free lock */ - sync - stw %r20, 0(%sr2,%r20) + stw,ma %r20, 0(%sr2,%r20) /* Enable interrupts */ ssm PSW_SM_I, %r0 /* Return to userspace, set no error */ @@ -868,8 +865,7 @@ cas2_end: 22: /* Error occurred on load or store */ /* Free lock */ - sync - stw %r20, 0(%sr2,%r20) + stw,ma %r20, 0(%sr2,%r20) ssm PSW_SM_I, %r0 ldo 1(%r0),%r28 b lws_exit