Patch "c6x/ptrace: Remove useless PTRACE_SETREGSET implementation" has been added to the 3.18-stable tree

This is a note to let you know that I've just added the patch titled

c6x/ptrace: Remove useless PTRACE_SETREGSET implementation

to the 3.18-stable tree which can be found at:
http://www.kernel.org/git/?p=linux/kernel/git/stable/stable-queue.git;a=summary

The filename of the patch is:
c6x-ptrace-remove-useless-ptrace_setregset-implementation.patch
and it can be found in the queue-3.18 subdirectory.

If you, or anyone else, feels it should not be added to the stable tree, please let <[email protected]> know about it.

From: Dave Martin <[email protected]>
Date: Mon, 27 Mar 2017 15:10:53 +0100
Subject: c6x/ptrace: Remove useless PTRACE_SETREGSET implementation

From: Dave Martin <[email protected]>

commit fb411b837b587a32046dc4f369acb93a10b1def8 upstream.

gpr_set won't work correctly and can never have been tested, and the correct behaviour is not clear due to the endianness-dependent task layout.

So, just remove it. The core code will now return -EOPNOTSUPPORT when trying to set NT_PRSTATUS on this architecture until/unless a correct implementation is supplied.

---
 arch/c6x/kernel/ptrace.c |   41 -----------------------------------------
 1 file changed, 41 deletions(-)

@@ -69,46 +69,6 @@ static int gpr_get(struct task_struct *t
 				   0, sizeof(*regs));
 }
 
-static int gpr_set(struct task_struct *target,
-		   const struct user_regset *regset,
-		   unsigned int pos, unsigned int count,
-		   const void *kbuf, const void __user *ubuf)
-{
-	int ret;
-	struct pt_regs *regs = task_pt_regs(target);
-
-	/* Don't copyin TSR or CSR */
-	ret = user_regset_copyin(&pos, &count, &kbuf, &ubuf,
-				 &regs,
-				 0, PT_TSR * sizeof(long));
-	if (ret)
-		return ret;
-
-	ret = user_regset_copyin_ignore(&pos, &count, &kbuf, &ubuf,
-					PT_TSR * sizeof(long),
-					(PT_TSR + 1) * sizeof(long));
-	if (ret)
-		return ret;
-
-	ret = user_regset_copyin(&pos, &count, &kbuf, &ubuf,
-				 &regs,
-				 (PT_TSR + 1) * sizeof(long),
-				 PT_CSR * sizeof(long));
-	if (ret)
-		return ret;
-
-	ret = user_regset_copyin_ignore(&pos, &count, &kbuf, &ubuf,
-					PT_CSR * sizeof(long),
-					(PT_CSR + 1) * sizeof(long));
-	if (ret)
-		return ret;
-
-	ret = user_regset_copyin(&pos, &count, &kbuf, &ubuf,
-				 &regs,
-				 (PT_CSR + 1) * sizeof(long), -1);
-	return ret;
-}
-
 enum c6x_regset {
 	REGSET_GPR,
 };

@@ -120,7 +80,6 @@ static const struct user_regset c6x_regs
 		.size = sizeof(u32),
 		.align = sizeof(u32),
 		.get = gpr_get,
-		.set = gpr_set
 	},
 };
 

Patches currently in stable-queue which might be from [email protected] are

queue-3.18/metag-ptrace-reject-partial-nt_metag_rpipe-writes.patch queue-3.18/metag-ptrace-preserve-previous-registers-for-short-regset-write.patch queue-3.18/metag-ptrace-provide-default-txstatus-for-short-nt_prstatus.patch queue-3.18/c6x-ptrace-remove-useless-ptrace_setregset-implementation.patch queue-3.18/mips-ptrace-preserve-previous-registers-for-short-regset-write.patch queue-3.18/sparc-ptrace-preserve-previous-registers-for-short-regset-write.patch