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-rw-r--r--arch/tile/kernel/compat_signal.c6
-rw-r--r--arch/tile/kernel/intvec_32.S24
-rw-r--r--arch/tile/kernel/process.c8
-rw-r--r--arch/tile/kernel/signal.c10
4 files changed, 36 insertions, 12 deletions
diff --git a/arch/tile/kernel/compat_signal.c b/arch/tile/kernel/compat_signal.c
index 543d6a33aa2..dbb0dfc7bec 100644
--- a/arch/tile/kernel/compat_signal.c
+++ b/arch/tile/kernel/compat_signal.c
@@ -290,12 +290,12 @@ long compat_sys_sigaltstack(const struct compat_sigaltstack __user *uss_ptr,
return ret;
}
+/* The assembly shim for this function arranges to ignore the return value. */
long compat_sys_rt_sigreturn(struct pt_regs *regs)
{
struct compat_rt_sigframe __user *frame =
(struct compat_rt_sigframe __user *) compat_ptr(regs->sp);
sigset_t set;
- long r0;
if (!access_ok(VERIFY_READ, frame, sizeof(*frame)))
goto badframe;
@@ -308,13 +308,13 @@ long compat_sys_rt_sigreturn(struct pt_regs *regs)
recalc_sigpending();
spin_unlock_irq(&current->sighand->siglock);
- if (restore_sigcontext(regs, &frame->uc.uc_mcontext, &r0))
+ if (restore_sigcontext(regs, &frame->uc.uc_mcontext))
goto badframe;
if (compat_sys_sigaltstack(&frame->uc.uc_stack, NULL, regs) != 0)
goto badframe;
- return r0;
+ return 0;
badframe:
force_sig(SIGSEGV, current);
diff --git a/arch/tile/kernel/intvec_32.S b/arch/tile/kernel/intvec_32.S
index f5821626247..5eed4a02bf6 100644
--- a/arch/tile/kernel/intvec_32.S
+++ b/arch/tile/kernel/intvec_32.S
@@ -1342,8 +1342,8 @@ handle_syscall:
lw r20, r20
/* Jump to syscall handler. */
- jalr r20; .Lhandle_syscall_link:
- FEEDBACK_REENTER(handle_syscall)
+ jalr r20
+.Lhandle_syscall_link: /* value of "lr" after "jalr r20" above */
/*
* Write our r0 onto the stack so it gets restored instead
@@ -1352,6 +1352,9 @@ handle_syscall:
PTREGS_PTR(r29, PTREGS_OFFSET_REG(0))
sw r29, r0
+.Lsyscall_sigreturn_skip:
+ FEEDBACK_REENTER(handle_syscall)
+
/* Do syscall trace again, if requested. */
lw r30, r31
andi r30, r30, _TIF_SYSCALL_TRACE
@@ -1536,9 +1539,24 @@ STD_ENTRY_LOCAL(bad_intr)
}; \
STD_ENDPROC(_##x)
+/*
+ * Special-case sigreturn to not write r0 to the stack on return.
+ * This is technically more efficient, but it also avoids difficulties
+ * in the 64-bit OS when handling 32-bit compat code, since we must not
+ * sign-extend r0 for the sigreturn return-value case.
+ */
+#define PTREGS_SYSCALL_SIGRETURN(x, reg) \
+ STD_ENTRY(_##x); \
+ addli lr, lr, .Lsyscall_sigreturn_skip - .Lhandle_syscall_link; \
+ { \
+ PTREGS_PTR(reg, PTREGS_OFFSET_BASE); \
+ j x \
+ }; \
+ STD_ENDPROC(_##x)
+
PTREGS_SYSCALL(sys_execve, r3)
PTREGS_SYSCALL(sys_sigaltstack, r2)
-PTREGS_SYSCALL(sys_rt_sigreturn, r0)
+PTREGS_SYSCALL_SIGRETURN(sys_rt_sigreturn, r0)
PTREGS_SYSCALL(sys_cmpxchg_badaddr, r1)
/* Save additional callee-saves to pt_regs, put address in r4 and jump. */
diff --git a/arch/tile/kernel/process.c b/arch/tile/kernel/process.c
index 8430f45daea..e90eb53173b 100644
--- a/arch/tile/kernel/process.c
+++ b/arch/tile/kernel/process.c
@@ -212,6 +212,13 @@ int copy_thread(unsigned long clone_flags, unsigned long sp,
childregs->sp = sp; /* override with new user stack pointer */
/*
+ * If CLONE_SETTLS is set, set "tp" in the new task to "r4",
+ * which is passed in as arg #5 to sys_clone().
+ */
+ if (clone_flags & CLONE_SETTLS)
+ childregs->tp = regs->regs[4];
+
+ /*
* Copy the callee-saved registers from the passed pt_regs struct
* into the context-switch callee-saved registers area.
* This way when we start the interrupt-return sequence, the
@@ -539,6 +546,7 @@ struct task_struct *__sched _switch_to(struct task_struct *prev,
return __switch_to(prev, next, next_current_ksp0(next));
}
+/* Note there is an implicit fifth argument if (clone_flags & CLONE_SETTLS). */
SYSCALL_DEFINE5(clone, unsigned long, clone_flags, unsigned long, newsp,
void __user *, parent_tidptr, void __user *, child_tidptr,
struct pt_regs *, regs)
diff --git a/arch/tile/kernel/signal.c b/arch/tile/kernel/signal.c
index 757407e3669..1260321155f 100644
--- a/arch/tile/kernel/signal.c
+++ b/arch/tile/kernel/signal.c
@@ -52,7 +52,7 @@ SYSCALL_DEFINE3(sigaltstack, const stack_t __user *, uss,
*/
int restore_sigcontext(struct pt_regs *regs,
- struct sigcontext __user *sc, long *pr0)
+ struct sigcontext __user *sc)
{
int err = 0;
int i;
@@ -75,17 +75,15 @@ int restore_sigcontext(struct pt_regs *regs,
regs->faultnum = INT_SWINT_1_SIGRETURN;
- err |= __get_user(*pr0, &sc->gregs[0]);
return err;
}
-/* sigreturn() returns long since it restores r0 in the interrupted code. */
+/* The assembly shim for this function arranges to ignore the return value. */
SYSCALL_DEFINE1(rt_sigreturn, struct pt_regs *, regs)
{
struct rt_sigframe __user *frame =
(struct rt_sigframe __user *)(regs->sp);
sigset_t set;
- long r0;
if (!access_ok(VERIFY_READ, frame, sizeof(*frame)))
goto badframe;
@@ -98,13 +96,13 @@ SYSCALL_DEFINE1(rt_sigreturn, struct pt_regs *, regs)
recalc_sigpending();
spin_unlock_irq(&current->sighand->siglock);
- if (restore_sigcontext(regs, &frame->uc.uc_mcontext, &r0))
+ if (restore_sigcontext(regs, &frame->uc.uc_mcontext))
goto badframe;
if (do_sigaltstack(&frame->uc.uc_stack, NULL, regs->sp) == -EFAULT)
goto badframe;
- return r0;
+ return 0;
badframe:
force_sig(SIGSEGV, current);
generated by cgit v1.2.3-70-g09d2 (git 2.46.0) at 2024-11-16 00:02:38 +0000