From: Rusty Lynch <rusty.lynch@intel.com>
Date: Mon, 27 Jun 2005 22:17:15 +0000 (-0700)
Subject: [PATCH] kprobes/ia64: refuse inserting kprobe on slot 1
X-Git-Url: http://git.osdn.net/view?a=commitdiff_plain;h=a528e21c235862cc1ae50e7809eb9116dc40ea0c;p=sagit-ice-cold%2Fkernel_xiaomi_msm8998.git

[PATCH] kprobes/ia64: refuse inserting kprobe on slot 1

Without the ability to atomically write 16 bytes, we can not update the
middle slot of a bundle, slot 1, unless we stop the machine first.  This
patch will ensure the ability to robustly insert and remove a kprobe by
refusing to insert a kprobe on slot 1 until a mechanism is in place to
safely handle this case.

Signed-off-by: Rusty Lynch <rusty.lynch@intel.com>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
---

diff --git a/arch/ia64/kernel/kprobes.c b/arch/ia64/kernel/kprobes.c
index c97e18e634ca..ec2ceade12b0 100644
--- a/arch/ia64/kernel/kprobes.c
+++ b/arch/ia64/kernel/kprobes.c
@@ -270,6 +270,13 @@ static int valid_kprobe_addr(int template, int slot, unsigned long addr)
 				addr);
 		return -EINVAL;
 	}
+
+	if (slot == 1 && bundle_encoding[template][1] != L) {
+		printk(KERN_WARNING "Inserting kprobes on slot #1 "
+		       "is not supported\n");
+		return -EINVAL;
+	}
+
 	return 0;
 }