[PATCH v2] powerpc: Wire up clone3 syscall
From: Michael Ellerman <mpe@ellerman.id.au>
Date: 2019-07-24 14:03:08
Wire up the new clone3 syscall added in commit 7f192e3cd316 ("fork:
add clone3").
This requires a ppc_clone3 wrapper, in order to save the non-volatile
GPRs before calling into the generic syscall code. Otherwise we hit
the BUG_ON in CHECK_FULL_REGS in copy_thread().
Lightly tested using Christian's test code on a Power8 LE VM.
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
---
arch/powerpc/include/asm/unistd.h | 1 +
arch/powerpc/kernel/entry_32.S | 8 ++++++++
arch/powerpc/kernel/entry_64.S | 5 +++++
arch/powerpc/kernel/syscalls/syscall.tbl | 1 +
4 files changed, 15 insertions(+)
v2: Add the wrapper for 32-bit as well, don't allow SPU programs to call
clone3 (switch ABI to nospu).
v1: https://lore.kernel.org/r/20190722132231.10169-1-mpe@ellerman.id.au
diff --git a/arch/powerpc/include/asm/unistd.h b/arch/powerpc/include/asm/unistd.h
index 68473c3c471c..b0720c7c3fcf 100644
--- a/arch/powerpc/include/asm/unistd.h
+++ b/arch/powerpc/include/asm/unistd.h@@ -49,6 +49,7 @@ #define __ARCH_WANT_SYS_FORK #define __ARCH_WANT_SYS_VFORK #define __ARCH_WANT_SYS_CLONE +#define __ARCH_WANT_SYS_CLONE3 #endif /* __ASSEMBLY__ */ #endif /* _ASM_POWERPC_UNISTD_H_ */
diff --git a/arch/powerpc/kernel/entry_32.S b/arch/powerpc/kernel/entry_32.S
index 85fdb6d879f1..54fab22c9a43 100644
--- a/arch/powerpc/kernel/entry_32.S
+++ b/arch/powerpc/kernel/entry_32.S@@ -597,6 +597,14 @@ END_FTR_SECTION_IFSET(CPU_FTR_NEED_PAIRED_STWCX) stw r0,_TRAP(r1) /* register set saved */ b sys_clone + .globl ppc_clone3 +ppc_clone3: + SAVE_NVGPRS(r1) + lwz r0,_TRAP(r1) + rlwinm r0,r0,0,0,30 /* clear LSB to indicate full */ + stw r0,_TRAP(r1) /* register set saved */ + b sys_clone3 + .globl ppc_swapcontext ppc_swapcontext: SAVE_NVGPRS(r1)
diff --git a/arch/powerpc/kernel/entry_64.S b/arch/powerpc/kernel/entry_64.S
index d9105fcf4021..0a0b5310f54a 100644
--- a/arch/powerpc/kernel/entry_64.S
+++ b/arch/powerpc/kernel/entry_64.S@@ -487,6 +487,11 @@ _GLOBAL(ppc_clone) bl sys_clone b .Lsyscall_exit +_GLOBAL(ppc_clone3) + bl save_nvgprs + bl sys_clone3 + b .Lsyscall_exit + _GLOBAL(ppc32_swapcontext) bl save_nvgprs bl compat_sys_swapcontext
diff --git a/arch/powerpc/kernel/syscalls/syscall.tbl b/arch/powerpc/kernel/syscalls/syscall.tbl
index f2c3bda2d39f..43f736ed47f2 100644
--- a/arch/powerpc/kernel/syscalls/syscall.tbl
+++ b/arch/powerpc/kernel/syscalls/syscall.tbl@@ -516,3 +516,4 @@ 432 common fsmount sys_fsmount 433 common fspick sys_fspick 434 common pidfd_open sys_pidfd_open +435 nospu clone3 ppc_clone3
--
2.20.1