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authorLinus Torvalds <torvalds@linux-foundation.org>2012-12-12 12:22:13 -0800
committerLinus Torvalds <torvalds@linux-foundation.org>2012-12-12 12:22:13 -0800
commit9977d9b379cb77e0f67bd6f4563618106e58e11d (patch)
tree0191accfddf578edb52c69c933d64521e3dce297 /arch/x86/kernel
parentcf4af01221579a4e895f43dbfc47598fbfc5a731 (diff)
parent541880d9a2c7871f6370071d55aa6662d329c51e (diff)
Merge branch 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/viro/signal
Pull big execve/kernel_thread/fork unification series from Al Viro: "All architectures are converted to new model. Quite a bit of that stuff is actually shared with architecture trees; in such cases it's literally shared branch pulled by both, not a cherry-pick. A lot of ugliness and black magic is gone (-3KLoC total in this one): - kernel_thread()/kernel_execve()/sys_execve() redesign. We don't do syscalls from kernel anymore for either kernel_thread() or kernel_execve(): kernel_thread() is essentially clone(2) with callback run before we return to userland, the callbacks either never return or do successful do_execve() before returning. kernel_execve() is a wrapper for do_execve() - it doesn't need to do transition to user mode anymore. As a result kernel_thread() and kernel_execve() are arch-independent now - they live in kernel/fork.c and fs/exec.c resp. sys_execve() is also in fs/exec.c and it's completely architecture-independent. - daemonize() is gone, along with its parts in fs/*.c - struct pt_regs * is no longer passed to do_fork/copy_process/ copy_thread/do_execve/search_binary_handler/->load_binary/do_coredump. - sys_fork()/sys_vfork()/sys_clone() unified; some architectures still need wrappers (ones with callee-saved registers not saved in pt_regs on syscall entry), but the main part of those suckers is in kernel/fork.c now." * 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/viro/signal: (113 commits) do_coredump(): get rid of pt_regs argument print_fatal_signal(): get rid of pt_regs argument ptrace_signal(): get rid of unused arguments get rid of ptrace_signal_deliver() arguments new helper: signal_pt_regs() unify default ptrace_signal_deliver flagday: kill pt_regs argument of do_fork() death to idle_regs() don't pass regs to copy_process() flagday: don't pass regs to copy_thread() bfin: switch to generic vfork, get rid of pointless wrappers xtensa: switch to generic clone() openrisc: switch to use of generic fork and clone unicore32: switch to generic clone(2) score: switch to generic fork/vfork/clone c6x: sanitize copy_thread(), get rid of clone(2) wrapper, switch to generic clone() take sys_fork/sys_vfork/sys_clone prototypes to linux/syscalls.h mn10300: switch to generic fork/vfork/clone h8300: switch to generic fork/vfork/clone tile: switch to generic clone() ... Conflicts: arch/microblaze/include/asm/Kbuild
Diffstat (limited to 'arch/x86/kernel')
-rw-r--r--arch/x86/kernel/cpu/common.c9
-rw-r--r--arch/x86/kernel/entry_32.S18
-rw-r--r--arch/x86/kernel/entry_64.S22
-rw-r--r--arch/x86/kernel/process.c30
-rw-r--r--arch/x86/kernel/process_32.c12
-rw-r--r--arch/x86/kernel/process_64.c10
6 files changed, 30 insertions, 71 deletions
diff --git a/arch/x86/kernel/cpu/common.c b/arch/x86/kernel/cpu/common.c
index ca165ac6793..9c3ab43a695 100644
--- a/arch/x86/kernel/cpu/common.c
+++ b/arch/x86/kernel/cpu/common.c
@@ -1173,15 +1173,6 @@ DEFINE_PER_CPU(struct task_struct *, fpu_owner_task);
DEFINE_PER_CPU_ALIGNED(struct stack_canary, stack_canary);
#endif
-/* Make sure %fs and %gs are initialized properly in idle threads */
-struct pt_regs * __cpuinit idle_regs(struct pt_regs *regs)
-{
- memset(regs, 0, sizeof(struct pt_regs));
- regs->fs = __KERNEL_PERCPU;
- regs->gs = __KERNEL_STACK_CANARY;
-
- return regs;
-}
#endif /* CONFIG_X86_64 */
/*
diff --git a/arch/x86/kernel/entry_32.S b/arch/x86/kernel/entry_32.S
index 88b725aa1d5..c763116c535 100644
--- a/arch/x86/kernel/entry_32.S
+++ b/arch/x86/kernel/entry_32.S
@@ -739,30 +739,12 @@ ENTRY(ptregs_##name) ; \
ENDPROC(ptregs_##name)
PTREGSCALL1(iopl)
-PTREGSCALL0(fork)
-PTREGSCALL0(vfork)
PTREGSCALL2(sigaltstack)
PTREGSCALL0(sigreturn)
PTREGSCALL0(rt_sigreturn)
PTREGSCALL2(vm86)
PTREGSCALL1(vm86old)
-/* Clone is an oddball. The 4th arg is in %edi */
-ENTRY(ptregs_clone)
- CFI_STARTPROC
- leal 4(%esp),%eax
- pushl_cfi %eax
- pushl_cfi PT_EDI(%eax)
- movl PT_EDX(%eax),%ecx
- movl PT_ECX(%eax),%edx
- movl PT_EBX(%eax),%eax
- call sys_clone
- addl $8,%esp
- CFI_ADJUST_CFA_OFFSET -8
- ret
- CFI_ENDPROC
-ENDPROC(ptregs_clone)
-
.macro FIXUP_ESPFIX_STACK
/*
* Switch back for ESPFIX stack to the normal zerobased stack
diff --git a/arch/x86/kernel/entry_64.S b/arch/x86/kernel/entry_64.S
index 31b46128a63..70641aff0c2 100644
--- a/arch/x86/kernel/entry_64.S
+++ b/arch/x86/kernel/entry_64.S
@@ -845,9 +845,25 @@ ENTRY(\label)
END(\label)
.endm
- PTREGSCALL stub_clone, sys_clone, %r8
- PTREGSCALL stub_fork, sys_fork, %rdi
- PTREGSCALL stub_vfork, sys_vfork, %rdi
+ .macro FORK_LIKE func
+ENTRY(stub_\func)
+ CFI_STARTPROC
+ popq %r11 /* save return address */
+ PARTIAL_FRAME 0
+ SAVE_REST
+ pushq %r11 /* put it back on stack */
+ FIXUP_TOP_OF_STACK %r11, 8
+ DEFAULT_FRAME 0 8 /* offset 8: return address */
+ call sys_\func
+ RESTORE_TOP_OF_STACK %r11, 8
+ ret $REST_SKIP /* pop extended registers */
+ CFI_ENDPROC
+END(stub_\func)
+ .endm
+
+ FORK_LIKE clone
+ FORK_LIKE fork
+ FORK_LIKE vfork
PTREGSCALL stub_sigaltstack, sys_sigaltstack, %rdx
PTREGSCALL stub_iopl, sys_iopl, %rsi
diff --git a/arch/x86/kernel/process.c b/arch/x86/kernel/process.c
index 2f99e312187..2ed787f15bf 100644
--- a/arch/x86/kernel/process.c
+++ b/arch/x86/kernel/process.c
@@ -262,36 +262,6 @@ void __switch_to_xtra(struct task_struct *prev_p, struct task_struct *next_p,
propagate_user_return_notify(prev_p, next_p);
}
-int sys_fork(struct pt_regs *regs)
-{
- return do_fork(SIGCHLD, regs->sp, regs, 0, NULL, NULL);
-}
-
-/*
- * This is trivial, and on the face of it looks like it
- * could equally well be done in user mode.
- *
- * Not so, for quite unobvious reasons - register pressure.
- * In user mode vfork() cannot have a stack frame, and if
- * done by calling the "clone()" system call directly, you
- * do not have enough call-clobbered registers to hold all
- * the information you need.
- */
-int sys_vfork(struct pt_regs *regs)
-{
- return do_fork(CLONE_VFORK | CLONE_VM | SIGCHLD, regs->sp, regs, 0,
- NULL, NULL);
-}
-
-long
-sys_clone(unsigned long clone_flags, unsigned long newsp,
- void __user *parent_tid, void __user *child_tid, struct pt_regs *regs)
-{
- if (!newsp)
- newsp = regs->sp;
- return do_fork(clone_flags, newsp, regs, 0, parent_tid, child_tid);
-}
-
/*
* Idle related variables and functions
*/
diff --git a/arch/x86/kernel/process_32.c b/arch/x86/kernel/process_32.c
index 44e0bff38e7..b5a8905785e 100644
--- a/arch/x86/kernel/process_32.c
+++ b/arch/x86/kernel/process_32.c
@@ -128,8 +128,7 @@ void release_thread(struct task_struct *dead_task)
}
int copy_thread(unsigned long clone_flags, unsigned long sp,
- unsigned long arg,
- struct task_struct *p, struct pt_regs *regs)
+ unsigned long arg, struct task_struct *p)
{
struct pt_regs *childregs = task_pt_regs(p);
struct task_struct *tsk;
@@ -138,7 +137,7 @@ int copy_thread(unsigned long clone_flags, unsigned long sp,
p->thread.sp = (unsigned long) childregs;
p->thread.sp0 = (unsigned long) (childregs+1);
- if (unlikely(!regs)) {
+ if (unlikely(p->flags & PF_KTHREAD)) {
/* kernel thread */
memset(childregs, 0, sizeof(struct pt_regs));
p->thread.ip = (unsigned long) ret_from_kernel_thread;
@@ -156,12 +155,13 @@ int copy_thread(unsigned long clone_flags, unsigned long sp,
memset(p->thread.ptrace_bps, 0, sizeof(p->thread.ptrace_bps));
return 0;
}
- *childregs = *regs;
+ *childregs = *current_pt_regs();
childregs->ax = 0;
- childregs->sp = sp;
+ if (sp)
+ childregs->sp = sp;
p->thread.ip = (unsigned long) ret_from_fork;
- task_user_gs(p) = get_user_gs(regs);
+ task_user_gs(p) = get_user_gs(current_pt_regs());
p->fpu_counter = 0;
p->thread.io_bitmap_ptr = NULL;
diff --git a/arch/x86/kernel/process_64.c b/arch/x86/kernel/process_64.c
index 16c6365e2b8..6e68a619496 100644
--- a/arch/x86/kernel/process_64.c
+++ b/arch/x86/kernel/process_64.c
@@ -146,8 +146,7 @@ static inline u32 read_32bit_tls(struct task_struct *t, int tls)
}
int copy_thread(unsigned long clone_flags, unsigned long sp,
- unsigned long arg,
- struct task_struct *p, struct pt_regs *regs)
+ unsigned long arg, struct task_struct *p)
{
int err;
struct pt_regs *childregs;
@@ -169,7 +168,7 @@ int copy_thread(unsigned long clone_flags, unsigned long sp,
savesegment(ds, p->thread.ds);
memset(p->thread.ptrace_bps, 0, sizeof(p->thread.ptrace_bps));
- if (unlikely(!regs)) {
+ if (unlikely(p->flags & PF_KTHREAD)) {
/* kernel thread */
memset(childregs, 0, sizeof(struct pt_regs));
childregs->sp = (unsigned long)childregs;
@@ -181,10 +180,11 @@ int copy_thread(unsigned long clone_flags, unsigned long sp,
childregs->flags = X86_EFLAGS_IF | X86_EFLAGS_BIT1;
return 0;
}
- *childregs = *regs;
+ *childregs = *current_pt_regs();
childregs->ax = 0;
- childregs->sp = sp;
+ if (sp)
+ childregs->sp = sp;
err = -ENOMEM;
memset(p->thread.ptrace_bps, 0, sizeof(p->thread.ptrace_bps));