Re: [PATCH 1/3] powerpc/uaccess: Switch __put_user_size_allowed() to __put_user_asm_goto()
Andreas Schwab writes: > # > # Automatically generated file; DO NOT EDIT. > # Linux/powerpc 5.10.0-rc1 Kernel Configuration > # > CONFIG_CC_VERSION_TEXT="gcc-4.9 (SUSE Linux) 4.9.3" So it seems to be a combination of GCC 4.9 and ... > # CONFIG_PPC_RADIX_MMU is not set That ^, which specifically causes PPC_KUAP=n. When PPC_KUAP=y allow_user_access() inlines an isync and mtspr, both of which contain a memory clobber, and that seems to hide the bug. I think for now we just have to stop using asm goto for put_user() on GCC 4.9. I'll send a patch for that. cheers
Re: [PATCH 1/3] powerpc/uaccess: Switch __put_user_size_allowed() to __put_user_asm_goto()
# # Automatically generated file; DO NOT EDIT. # Linux/powerpc 5.10.0-rc1 Kernel Configuration # CONFIG_CC_VERSION_TEXT="gcc-4.9 (SUSE Linux) 4.9.3" CONFIG_CC_IS_GCC=y CONFIG_GCC_VERSION=40903 CONFIG_LD_VERSION=23501 CONFIG_CLANG_VERSION=0 CONFIG_CC_CAN_LINK=y CONFIG_CC_CAN_LINK_STATIC=y CONFIG_CC_HAS_ASM_GOTO=y CONFIG_IRQ_WORK=y CONFIG_BUILDTIME_TABLE_SORT=y CONFIG_THREAD_INFO_IN_TASK=y # # General setup # CONFIG_INIT_ENV_ARG_LIMIT=32 # CONFIG_COMPILE_TEST is not set CONFIG_LOCALVERSION="" # CONFIG_LOCALVERSION_AUTO is not set CONFIG_BUILD_SALT="" CONFIG_HAVE_KERNEL_GZIP=y CONFIG_HAVE_KERNEL_XZ=y CONFIG_KERNEL_GZIP=y # CONFIG_KERNEL_XZ is not set CONFIG_DEFAULT_INIT="" CONFIG_DEFAULT_HOSTNAME="(none)" CONFIG_SWAP=y CONFIG_SYSVIPC=y CONFIG_SYSVIPC_SYSCTL=y CONFIG_POSIX_MQUEUE=y CONFIG_POSIX_MQUEUE_SYSCTL=y CONFIG_WATCH_QUEUE=y CONFIG_CROSS_MEMORY_ATTACH=y CONFIG_USELIB=y CONFIG_AUDIT=y CONFIG_HAVE_ARCH_AUDITSYSCALL=y CONFIG_AUDITSYSCALL=y # # IRQ subsystem # CONFIG_GENERIC_IRQ_SHOW=y CONFIG_GENERIC_IRQ_SHOW_LEVEL=y CONFIG_GENERIC_IRQ_MIGRATION=y CONFIG_IRQ_DOMAIN=y CONFIG_IRQ_FORCED_THREADING=y CONFIG_SPARSE_IRQ=y # CONFIG_GENERIC_IRQ_DEBUGFS is not set # end of IRQ subsystem CONFIG_GENERIC_TIME_VSYSCALL=y CONFIG_GENERIC_CLOCKEVENTS=y CONFIG_ARCH_HAS_TICK_BROADCAST=y CONFIG_GENERIC_CLOCKEVENTS_BROADCAST=y CONFIG_GENERIC_CMOS_UPDATE=y # # Timers subsystem # CONFIG_TICK_ONESHOT=y CONFIG_NO_HZ_COMMON=y # CONFIG_HZ_PERIODIC is not set CONFIG_NO_HZ_IDLE=y # CONFIG_NO_HZ_FULL is not set CONFIG_NO_HZ=y CONFIG_HIGH_RES_TIMERS=y # end of Timers subsystem # CONFIG_PREEMPT_NONE is not set CONFIG_PREEMPT_VOLUNTARY=y # CONFIG_PREEMPT is not set # # CPU/Task time and stats accounting # CONFIG_VIRT_CPU_ACCOUNTING=y # CONFIG_TICK_CPU_ACCOUNTING is not set CONFIG_VIRT_CPU_ACCOUNTING_NATIVE=y # CONFIG_VIRT_CPU_ACCOUNTING_GEN is not set CONFIG_BSD_PROCESS_ACCT=y CONFIG_BSD_PROCESS_ACCT_V3=y CONFIG_TASKSTATS=y CONFIG_TASK_DELAY_ACCT=y CONFIG_TASK_XACCT=y CONFIG_TASK_IO_ACCOUNTING=y CONFIG_PSI=y # CONFIG_PSI_DEFAULT_DISABLED is not set # end of CPU/Task time and stats accounting # CONFIG_CPU_ISOLATION is not set # # RCU Subsystem # CONFIG_TREE_RCU=y # CONFIG_RCU_EXPERT is not set CONFIG_SRCU=y CONFIG_TREE_SRCU=y CONFIG_TASKS_RCU_GENERIC=y CONFIG_TASKS_TRACE_RCU=y CONFIG_RCU_STALL_COMMON=y CONFIG_RCU_NEED_SEGCBLIST=y # end of RCU Subsystem CONFIG_BUILD_BIN2C=y CONFIG_IKCONFIG=y CONFIG_IKCONFIG_PROC=y # CONFIG_IKHEADERS is not set CONFIG_LOG_BUF_SHIFT=18 CONFIG_LOG_CPU_MAX_BUF_SHIFT=15 CONFIG_PRINTK_SAFE_LOG_BUF_SHIFT=13 # # Scheduler features # CONFIG_UCLAMP_TASK=y CONFIG_UCLAMP_BUCKETS_COUNT=5 # end of Scheduler features CONFIG_ARCH_SUPPORTS_NUMA_BALANCING=y CONFIG_CC_HAS_INT128=y CONFIG_CGROUPS=y CONFIG_PAGE_COUNTER=y CONFIG_MEMCG=y CONFIG_MEMCG_SWAP=y CONFIG_MEMCG_KMEM=y CONFIG_BLK_CGROUP=y CONFIG_CGROUP_WRITEBACK=y CONFIG_CGROUP_SCHED=y CONFIG_FAIR_GROUP_SCHED=y CONFIG_CFS_BANDWIDTH=y CONFIG_RT_GROUP_SCHED=y # CONFIG_UCLAMP_TASK_GROUP is not set CONFIG_CGROUP_PIDS=y CONFIG_CGROUP_RDMA=y CONFIG_CGROUP_FREEZER=y CONFIG_CGROUP_HUGETLB=y CONFIG_CPUSETS=y CONFIG_PROC_PID_CPUSET=y CONFIG_CGROUP_DEVICE=y CONFIG_CGROUP_CPUACCT=y CONFIG_CGROUP_PERF=y CONFIG_CGROUP_BPF=y # CONFIG_CGROUP_DEBUG is not set CONFIG_SOCK_CGROUP_DATA=y CONFIG_NAMESPACES=y CONFIG_UTS_NS=y CONFIG_IPC_NS=y CONFIG_USER_NS=y CONFIG_PID_NS=y CONFIG_NET_NS=y CONFIG_CHECKPOINT_RESTORE=y # CONFIG_SCHED_AUTOGROUP is not set # CONFIG_SYSFS_DEPRECATED is not set CONFIG_RELAY=y CONFIG_BLK_DEV_INITRD=y CONFIG_INITRAMFS_SOURCE="" CONFIG_RD_GZIP=y CONFIG_RD_BZIP2=y CONFIG_RD_LZMA=y CONFIG_RD_XZ=y CONFIG_RD_LZO=y CONFIG_RD_LZ4=y CONFIG_RD_ZSTD=y CONFIG_BOOT_CONFIG=y # CONFIG_CC_OPTIMIZE_FOR_PERFORMANCE is not set CONFIG_CC_OPTIMIZE_FOR_SIZE=y CONFIG_HAVE_LD_DEAD_CODE_DATA_ELIMINATION=y # CONFIG_LD_DEAD_CODE_DATA_ELIMINATION is not set CONFIG_SYSCTL=y CONFIG_SYSCTL_EXCEPTION_TRACE=y CONFIG_BPF=y CONFIG_EXPERT=y CONFIG_MULTIUSER=y CONFIG_SGETMASK_SYSCALL=y CONFIG_SYSFS_SYSCALL=y CONFIG_FHANDLE=y CONFIG_POSIX_TIMERS=y CONFIG_PRINTK=y CONFIG_PRINTK_NMI=y CONFIG_BUG=y CONFIG_ELF_CORE=y CONFIG_BASE_FULL=y CONFIG_FUTEX=y CONFIG_FUTEX_PI=y CONFIG_EPOLL=y CONFIG_SIGNALFD=y CONFIG_TIMERFD=y CONFIG_EVENTFD=y CONFIG_SHMEM=y CONFIG_AIO=y CONFIG_IO_URING=y CONFIG_ADVISE_SYSCALLS=y CONFIG_MEMBARRIER=y CONFIG_KALLSYMS=y CONFIG_KALLSYMS_ALL=y CONFIG_KALLSYMS_BASE_RELATIVE=y CONFIG_BPF_SYSCALL=y CONFIG_USERMODE_DRIVER=y # CONFIG_BPF_PRELOAD is not set CONFIG_USERFAULTFD=y CONFIG_ARCH_HAS_MEMBARRIER_CALLBACKS=y CONFIG_ARCH_HAS_MEMBARRIER_SYNC_CORE=y CONFIG_RSEQ=y # CONFIG_DEBUG_RSEQ is not set # CONFIG_EMBEDDED is not set CONFIG_HAVE_PERF_EVENTS=y # CONFIG_PC104 is not set # # Kernel Performance Events And Counters # CONFIG_PERF_EVENTS=y # end of Kernel Performance Events And Counters CONFIG_VM_EVENT_COUNTERS=y CONFIG_SLUB_DEBUG=y CONFIG_SLUB_MEMCG_SYSFS_ON=y # CONFIG_COMPAT_BRK is not set # CONFIG_SLAB is not set CONFIG_SLUB=y # CONFIG_SLOB is not set
Re: [PATCH 1/3] powerpc/uaccess: Switch __put_user_size_allowed() to __put_user_asm_goto()
Andreas Schwab writes: > On Okt 28 2020, Andreas Schwab wrote: > >> On Sep 04 2020, Christophe Leroy wrote: >> >>> __put_user_asm_goto() provides more flexibility to GCC and avoids using >>> a local variable to tell if the write succeeded or not. >>> GCC can then avoid implementing a cmp in the fast path. >> >> That breaks CLONE_CHILD_SETTID. I'm getting an assertion failure in >> __libc_fork (THREAD_GETMEM (self, tid) != ppid). > > This is what schedule_tail now looks like. As you can see, put_user has > become a nop: > > 455c <.schedule_tail>: > 455c: 7c 08 02 a6 mflrr0 > 4560: f8 01 00 10 std r0,16(r1) > 4564: f8 21 ff 91 stdur1,-112(r1) > 4568: 4b ff cd 4d bl 12b4 <.finish_task_switch> > 456c: 4b ff c0 99 bl 604 <.balance_callback> > 4570: e8 6d 01 88 ld r3,392(r13) > 4574: e9 23 06 b0 ld r9,1712(r3) > 4578: 2f a9 00 00 cmpdi cr7,r9,0 > 457c: 41 9e 00 14 beq cr7,4590 <.schedule_tail+0x34> > 4580: 38 80 00 00 li r4,0 > 4584: 38 a0 00 00 li r5,0 > 4588: 48 00 00 01 bl 4588 <.schedule_tail+0x2c> > 4588: R_PPC64_REL24 .__task_pid_nr_ns > 458c: 60 00 00 00 nop > 4590: 48 00 00 01 bl 4590 <.schedule_tail+0x34> > 4590: R_PPC64_REL24 .calculate_sigpending > 4594: 60 00 00 00 nop > 4598: 38 21 00 70 addir1,r1,112 > 459c: e8 01 00 10 ld r0,16(r1) > 45a0: 7c 08 03 a6 mtlrr0 > 45a4: 4e 80 00 20 blr Not for me, see below. What config and compiler are you using? cheers c0181aa0 : c0181aa0: 82 01 4c 3c addis r2,r12,386 c0181aa4: 60 1b 42 38 addir2,r2,7008 c0181aa8: a6 02 08 7c mflrr0 c0181aac: cd b5 ee 4b bl c006d078 <_mcount> c0181ab0: a6 02 08 7c mflrr0 c0181ab4: f8 ff e1 fb std r31,-8(r1) c0181ab8: 10 00 01 f8 std r0,16(r1) c0181abc: d1 ff 21 f8 stdur1,-48(r1) c0181ac0: c9 7d ff 4b bl c0179888 c0181ac4: 40 0a 23 e9 ld r9,2624(r3) c0181ac8: 00 00 a9 2f cmpdi cr7,r9,0 c0181acc: b4 00 9e 40 bne cr7,c0181b80 c0181ad0: 68 09 6d e8 ld r3,2408(r13) c0181ad4: 48 07 e3 eb ld r31,1864(r3) c0181ad8: 00 00 bf 2f cmpdi cr7,r31,0 c0181adc: 88 00 9e 41 beq cr7,c0181b64 c0181ae0: 00 00 a0 38 li r5,0 c0181ae4: 00 00 80 38 li r4,0 c0181ae8: 21 4b fe 4b bl c0166608 <__task_pid_nr_ns+0x8> c0181aec: 00 00 00 60 nop c0181af0: ff ff 20 39 li r9,-1 c0181af4: 00 03 29 79 clrldi r9,r9,12 c0181af8: 40 48 bf 7f cmpld cr7,r31,r9 c0181afc: 68 00 9d 41 bgt cr7,c0181b64 c0181b00: 01 00 29 39 addir9,r9,1 c0181b04: 50 48 3f 7d subfr9,r31,r9 c0181b08: 03 00 a9 2b cmpldi cr7,r9,3 c0181b0c: 58 00 9d 40 ble cr7,c0181b64 c0181b10: 02 00 42 3d addis r10,r2,2 c0181b14: 18 25 4a 39 addir10,r10,9496 c0181b18: 00 00 2a e9 ld r9,0(r10) c0181b1c: 22 00 29 e9 lwa r9,32(r9) c0181b20: 00 00 89 2f cmpwi cr7,r9,0 c0181b24: 24 00 9c 40 bge cr7,c0181b48 c0181b28: 2c 01 00 4c isync c0181b2c: 00 40 20 3d lis r9,16384 c0181b30: c6 07 29 79 rldicr r9,r9,32,31 c0181b34: a6 03 3d 7d mtspr 29,r9 # put_user() begins here c0181b38: 2c 01 00 4c isync c0181b3c: 00 00 2a e9 ld r9,0(r10) c0181b40: 22 00 29 e9 lwa r9,32(r9) c0181b44: 00 00 89 2f cmpwi cr7,r9,0 c0181b48: 00 00 7f 90 stw r3,0(r31) c0181b4c: 18 00 9c 40 bge cr7,c0181b64 c0181b50: 2c 01 00 4c isync c0181b54: ff ff 20 39 li r9,-1 c0181b58: 44 00 29 79 rldicr r9,r9,0,1 c0181b5c: a6 03 3d 7d mtspr 29,r9 c0181b60: 2c 01 00 4c isync c0181b64: b5 c9 fc 4b bl c014e518 c0181b68: 00 00 00 60 nop c0181b6c: 30 00 21 38 addir1,r1,48 c0181b70: 10 00 01 e8 ld r0,16(r1) c0181b74: f8 ff e1 eb
Re: [PATCH 1/3] powerpc/uaccess: Switch __put_user_size_allowed() to __put_user_asm_goto()
On Okt 28 2020, Michael Ellerman wrote: > What config and compiler are you using? gcc 4.9. Andreas. -- Andreas Schwab, sch...@linux-m68k.org GPG Key fingerprint = 7578 EB47 D4E5 4D69 2510 2552 DF73 E780 A9DA AEC1 "And now for something completely different."
Re: [PATCH 1/3] powerpc/uaccess: Switch __put_user_size_allowed() to __put_user_asm_goto()
On Okt 28 2020, Andreas Schwab wrote: > On Sep 04 2020, Christophe Leroy wrote: > >> __put_user_asm_goto() provides more flexibility to GCC and avoids using >> a local variable to tell if the write succeeded or not. >> GCC can then avoid implementing a cmp in the fast path. > > That breaks CLONE_CHILD_SETTID. I'm getting an assertion failure in > __libc_fork (THREAD_GETMEM (self, tid) != ppid). This is what schedule_tail now looks like. As you can see, put_user has become a nop: 455c <.schedule_tail>: 455c: 7c 08 02 a6 mflrr0 4560: f8 01 00 10 std r0,16(r1) 4564: f8 21 ff 91 stdur1,-112(r1) 4568: 4b ff cd 4d bl 12b4 <.finish_task_switch> 456c: 4b ff c0 99 bl 604 <.balance_callback> 4570: e8 6d 01 88 ld r3,392(r13) 4574: e9 23 06 b0 ld r9,1712(r3) 4578: 2f a9 00 00 cmpdi cr7,r9,0 457c: 41 9e 00 14 beq cr7,4590 <.schedule_tail+0x34> 4580: 38 80 00 00 li r4,0 4584: 38 a0 00 00 li r5,0 4588: 48 00 00 01 bl 4588 <.schedule_tail+0x2c> 4588: R_PPC64_REL24 .__task_pid_nr_ns 458c: 60 00 00 00 nop 4590: 48 00 00 01 bl 4590 <.schedule_tail+0x34> 4590: R_PPC64_REL24 .calculate_sigpending 4594: 60 00 00 00 nop 4598: 38 21 00 70 addir1,r1,112 459c: e8 01 00 10 ld r0,16(r1) 45a0: 7c 08 03 a6 mtlrr0 45a4: 4e 80 00 20 blr This is schedule_tail in 5.9: 455c <.schedule_tail>: 455c: 7c 08 02 a6 mflrr0 4560: fb c1 ff f0 std r30,-16(r1) 4564: fb e1 ff f8 std r31,-8(r1) 4568: f8 01 00 10 std r0,16(r1) 456c: f8 21 ff 81 stdur1,-128(r1) 4570: 4b ff cd 45 bl 12b4 <.finish_task_switch> 4574: 4b ff c0 91 bl 604 <.balance_callback> 4578: eb cd 01 88 ld r30,392(r13) 457c: eb fe 06 b0 ld r31,1712(r30) 4580: 2f bf 00 00 cmpdi cr7,r31,0 4584: 41 9e 00 2c beq cr7,45b0 <.schedule_tail+0x54> 4588: 7f c3 f3 78 mr r3,r30 458c: 38 80 00 00 li r4,0 4590: 38 a0 00 00 li r5,0 4594: 48 00 00 01 bl 4594 <.schedule_tail+0x38> 4594: R_PPC64_REL24 .__task_pid_nr_ns 4598: 60 00 00 00 nop 459c: e9 3e 0a b8 ld r9,2744(r30) 45a0: 7f bf 48 40 cmpld cr7,r31,r9 45a4: 41 9d 00 0c bgt cr7,45b0 <.schedule_tail+0x54> 45a8: 2b a9 00 03 cmpldi cr7,r9,3 45ac: 41 9d 00 14 bgt cr7,45c0 <.schedule_tail+0x64> 45b0: 48 00 00 01 bl 45b0 <.schedule_tail+0x54> 45b0: R_PPC64_REL24 .calculate_sigpending 45b4: 60 00 00 00 nop 45b8: 38 21 00 80 addir1,r1,128 45bc: 48 00 00 00 b 45bc <.schedule_tail+0x60> 45bc: R_PPC64_REL24 _restgpr0_30 45c0: 39 20 00 00 li r9,0 45c4: 90 7f 00 00 stw r3,0(r31) 45c8: 4b ff ff e8 b 45b0 <.schedule_tail+0x54> Andreas. -- Andreas Schwab, sch...@linux-m68k.org GPG Key fingerprint = 7578 EB47 D4E5 4D69 2510 2552 DF73 E780 A9DA AEC1 "And now for something completely different."
Re: [PATCH 1/3] powerpc/uaccess: Switch __put_user_size_allowed() to __put_user_asm_goto()
On Sep 04 2020, Christophe Leroy wrote: > __put_user_asm_goto() provides more flexibility to GCC and avoids using > a local variable to tell if the write succeeded or not. > GCC can then avoid implementing a cmp in the fast path. That breaks CLONE_CHILD_SETTID. I'm getting an assertion failure in __libc_fork (THREAD_GETMEM (self, tid) != ppid). Andreas. -- Andreas Schwab, sch...@linux-m68k.org GPG Key fingerprint = 7578 EB47 D4E5 4D69 2510 2552 DF73 E780 A9DA AEC1 "And now for something completely different."
Re: [PATCH 1/3] powerpc/uaccess: Switch __put_user_size_allowed() to __put_user_asm_goto()
On Fri, 4 Sep 2020 11:01:30 + (UTC), Christophe Leroy wrote: > __put_user_asm_goto() provides more flexibility to GCC and avoids using > a local variable to tell if the write succeeded or not. > GCC can then avoid implementing a cmp in the fast path. > > See the difference for a small function like the PPC64 version of > save_general_regs() in arch/powerpc/kernel/signal_32.c: > > [...] Applied to powerpc/next. [1/3] powerpc/uaccess: Switch __put_user_size_allowed() to __put_user_asm_goto() https://git.kernel.org/powerpc/c/ee0a49a6870ea75e25b4d4984c1bb6b3b7c65f2b [2/3] powerpc/uaccess: Switch __patch_instruction() to __put_user_asm_goto() https://git.kernel.org/powerpc/c/e64ac41ab0c510b3f85199a585eb886cad92fb19 [3/3] powerpc/uaccess: Remove __put_user_asm() and __put_user_asm2() https://git.kernel.org/powerpc/c/7fdf966bed155b214f4f1f9b67825a40b2e9b998 cheers
[PATCH 1/3] powerpc/uaccess: Switch __put_user_size_allowed() to __put_user_asm_goto()
__put_user_asm_goto() provides more flexibility to GCC and avoids using
a local variable to tell if the write succeeded or not.
GCC can then avoid implementing a cmp in the fast path.
See the difference for a small function like the PPC64 version of
save_general_regs() in arch/powerpc/kernel/signal_32.c:
Before the patch (unreachable nop removed):
0c10 <.save_general_regs>:
c10: 39 20 00 2c li r9,44
c14: 39 40 00 00 li r10,0
c18: 7d 29 03 a6 mtctr r9
c1c: 38 c0 00 00 li r6,0
c20: 48 00 00 14 b c34 <.save_general_regs+0x24>
c30: 42 40 00 40 bdz c70 <.save_general_regs+0x60>
c34: 28 2a 00 27 cmpldi r10,39
c38: 7c c8 33 78 mr r8,r6
c3c: 79 47 1f 24 rldicr r7,r10,3,60
c40: 39 20 00 01 li r9,1
c44: 41 82 00 0c beq c50 <.save_general_regs+0x40>
c48: 7d 23 38 2a ldx r9,r3,r7
c4c: 79 29 00 20 clrldi r9,r9,32
c50: 91 24 00 00 stw r9,0(r4)
c54: 2c 28 00 00 cmpdi r8,0
c58: 39 4a 00 01 addir10,r10,1
c5c: 38 84 00 04 addir4,r4,4
c60: 41 82 ff d0 beq c30 <.save_general_regs+0x20>
c64: 38 60 ff f2 li r3,-14
c68: 4e 80 00 20 blr
c70: 38 60 00 00 li r3,0
c74: 4e 80 00 20 blr
<.fixup>:
cc: 39 00 ff f2 li r8,-14
d0: 48 00 00 00 b d0 <.fixup+0xd0>
d0: R_PPC64_REL24 .text+0xc54
After the patch:
1490 <.save_general_regs>:
1490: 39 20 00 2c li r9,44
1494: 39 40 00 00 li r10,0
1498: 7d 29 03 a6 mtctr r9
149c: 60 00 00 00 nop
14a0: 28 2a 00 27 cmpldi r10,39
14a4: 79 48 1f 24 rldicr r8,r10,3,60
14a8: 39 20 00 01 li r9,1
14ac: 41 82 00 0c beq 14b8 <.save_general_regs+0x28>
14b0: 7d 23 40 2a ldx r9,r3,r8
14b4: 79 29 00 20 clrldi r9,r9,32
14b8: 91 24 00 00 stw r9,0(r4)
14bc: 39 4a 00 01 addir10,r10,1
14c0: 38 84 00 04 addir4,r4,4
14c4: 42 00 ff dc bdnz14a0 <.save_general_regs+0x10>
14c8: 38 60 00 00 li r3,0
14cc: 4e 80 00 20 blr
14d0: 38 60 ff f2 li r3,-14
14d4: 4e 80 00 20 blr
Signed-off-by: Christophe Leroy
---
arch/powerpc/include/asm/uaccess.h | 14 +++---
1 file changed, 7 insertions(+), 7 deletions(-)
diff --git a/arch/powerpc/include/asm/uaccess.h
b/arch/powerpc/include/asm/uaccess.h
index a5cfe867fbdc..96d1c144f92b 100644
--- a/arch/powerpc/include/asm/uaccess.h
+++ b/arch/powerpc/include/asm/uaccess.h
@@ -189,14 +189,14 @@ extern long __put_user_bad(void);
#define __put_user_size_allowed(x, ptr, size, retval) \
do { \
+ __label__ __pu_failed; \
+ \
retval = 0; \
- switch (size) { \
- case 1: __put_user_asm(x, ptr, retval, "stb"); break; \
- case 2: __put_user_asm(x, ptr, retval, "sth"); break; \
- case 4: __put_user_asm(x, ptr, retval, "stw"); break; \
- case 8: __put_user_asm2(x, ptr, retval); break; \
- default: __put_user_bad();\
- } \
+ __put_user_size_goto(x, ptr, size, __pu_failed);\
+ break; \
+ \
+__pu_failed: \
+ retval = -EFAULT; \
} while (0)
#define __put_user_size(x, ptr, size, retval) \
--
2.25.0
