From: Ananth N Mavinakayanahalli <ananth@in.ibm.com>
To: lkml <linux-kernel@vger.kernel.org>
Cc: ppcdev <linuxppc-dev@lists.ozlabs.org>,
oleg@redhat.com, Srikar Dronamraju <srikar@linux.vnet.ibm.com>
Subject: [PATCH 2/3] uprobes/powerpc: teach uprobes to ignore gdb breakpoints
Date: Fri, 22 Mar 2013 17:15:43 +0530 [thread overview]
Message-ID: <20130322114543.GH26183@in.ibm.com> (raw)
In-Reply-To: <20130322114446.GG26183@in.ibm.com>
From: Ananth N Mavinakayanahalli <ananth@in.ibm.com>
Powerpc has many trap variants that could be used by entities like gdb.
Currently, running gdb on a program being traced by uprobes causes an
endless loop since uprobes doesn't understand that the trap was inserted
by some other entity and a SIGTRAP needs to be delivered.
Teach uprobes to ignore breakpoints that do not belong to it.
Signed-off-by: Ananth N Mavinakayanahalli <ananth@in.ibm.com>
---
arch/powerpc/kernel/uprobes.c | 10 ++++++++++
1 file changed, 10 insertions(+)
Index: linux-3.9-rc3/arch/powerpc/kernel/uprobes.c
===================================================================
--- linux-3.9-rc3.orig/arch/powerpc/kernel/uprobes.c
+++ linux-3.9-rc3/arch/powerpc/kernel/uprobes.c
@@ -31,6 +31,16 @@
#define UPROBE_TRAP_NR UINT_MAX
/**
+ * is_trap_insn - check if the instruction is a trap variant
+ * @insn: instruction to be checked.
+ * Returns true if @insn is a trap variant.
+ */
+bool is_trap_insn(uprobe_opcode_t *insn)
+{
+ return (is_trap(*insn));
+}
+
+/**
* arch_uprobe_analyze_insn
* @mm: the probed address space.
* @arch_uprobe: the probepoint information.
next prev parent reply other threads:[~2013-03-22 11:46 UTC|newest]
Thread overview: 5+ messages / expand[flat|nested] mbox.gz Atom feed top
2013-03-22 11:44 [PATCH 1/3] uprobes: add trap variant helper Ananth N Mavinakayanahalli
2013-03-22 11:45 ` Ananth N Mavinakayanahalli [this message]
2013-03-22 11:46 ` [PATCH 3/3] uprobes/powerpc: ignore trap variants during register Ananth N Mavinakayanahalli
2013-03-22 14:54 ` [PATCH 1/3] uprobes: add trap variant helper Oleg Nesterov
2013-03-22 15:07 ` Ananth N Mavinakayanahalli
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