Commit 0a592281 authored by Linus Torvalds's avatar Linus Torvalds
Browse files

Merge git://git.kernel.org/pub/scm/linux/kernel/git/cmetcalf/linux-tile 

* git://git.kernel.org/pub/scm/linux/kernel/git/cmetcalf/linux-tile:
  arch/tile: handle rt_sigreturn() more cleanly
  arch/tile: handle CLONE_SETTLS in copy_thread(), not user space
parents 2ba16c4f 81711cee

arch/tile/include/asm/signal.h

+1 −1
Original line number Diff line number Diff line
@@ -25,7 +25,7 @@ 


#if defined(__KERNEL__) && !defined(__ASSEMBLY__)

struct pt_regs;

int restore_sigcontext(struct pt_regs *, struct sigcontext __user *, long *);

int restore_sigcontext(struct pt_regs *, struct sigcontext __user *);

int setup_sigcontext(struct sigcontext __user *, struct pt_regs *);

void do_signal(struct pt_regs *regs);

#endif

arch/tile/kernel/compat_signal.c

+3 −3
Original line number Diff line number Diff line
@@ -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);

arch/tile/kernel/intvec_32.S

+21 −3
Original line number Diff line number Diff line
@@ -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. */

arch/tile/kernel/process.c

+8 −0
Original line number Diff line number Diff line
@@ -211,6 +211,13 @@ int copy_thread(unsigned long clone_flags, unsigned long sp, 
	childregs->regs[0] = 0;         /* return value is zero */

	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.
@@ -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)

arch/tile/kernel/signal.c

+4 −6
Original line number Diff line number Diff line
@@ -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);