From: Anton Blanchard <anton@samba.org>
To: benh@kernel.crashing.org, paulus@samba.org, Ulrich.Weigand@de.ibm.com
Cc: linuxppc-dev@lists.ozlabs.org
Subject: [PATCH 1/8] powerpc: PTRACE_PEEKUSR always returns FPR0
Date: Thu, 12 Dec 2013 15:59:34 +1100 [thread overview]
Message-ID: <1386824381-14032-2-git-send-email-anton@samba.org> (raw)
In-Reply-To: <1386824381-14032-1-git-send-email-anton@samba.org>
From: Ulrich Weigand <Ulrich.Weigand@de.ibm.com>
There is a bug in using ptrace to access FPRs via PTRACE_PEEKUSR /
PTRACE_POKEUSR. In effect, trying to access any of the FPRs always
really accesses FPR0, which does seriously break debugging :-)
The problem seems to have been introduced by commit 3ad26e5c4459d
(Merge branch 'for-kvm' into next).
[ It is indeed a merge conflict between Paul's FPU/VSX state rework
and my LE patches - Anton ]
Signed-off-by: Ulrich Weigand <Ulrich.Weigand@de.ibm.com>
Signed-off-by: Anton Blanchard <anton@samba.org>
---
arch/powerpc/kernel/ptrace.c | 4 ++--
1 file changed, 2 insertions(+), 2 deletions(-)
diff --git a/arch/powerpc/kernel/ptrace.c b/arch/powerpc/kernel/ptrace.c
index 75fb404..2e3d2bf 100644
--- a/arch/powerpc/kernel/ptrace.c
+++ b/arch/powerpc/kernel/ptrace.c
@@ -1555,7 +1555,7 @@ long arch_ptrace(struct task_struct *child, long request,
flush_fp_to_thread(child);
if (fpidx < (PT_FPSCR - PT_FPR0))
- memcpy(&tmp, &child->thread.fp_state.fpr,
+ memcpy(&tmp, &child->thread.TS_FPR(fpidx),
sizeof(long));
else
tmp = child->thread.fp_state.fpscr;
@@ -1588,7 +1588,7 @@ long arch_ptrace(struct task_struct *child, long request,
flush_fp_to_thread(child);
if (fpidx < (PT_FPSCR - PT_FPR0))
- memcpy(&child->thread.fp_state.fpr, &data,
+ memcpy(&child->thread.TS_FPR(fpidx), &data,
sizeof(long));
else
child->thread.fp_state.fpscr = data;
--
1.8.3.2
next prev parent reply other threads:[~2013-12-12 4:59 UTC|newest]
Thread overview: 11+ messages / expand[flat|nested] mbox.gz Atom feed top
2013-12-12 4:59 [PATCH 0/8] ppc64 little endian bug fixes Anton Blanchard
2013-12-12 4:59 ` Anton Blanchard [this message]
2013-12-12 4:59 ` [PATCH 2/8] powerpc: Fix endian issue in setup-common.c Anton Blanchard
2013-12-12 4:59 ` [PATCH 3/8] powerpc: Fix topology core_id endian issue on LE builds Anton Blanchard
2013-12-12 4:59 ` [PATCH 4/8] powerpc/pseries: Fix endian issues in /proc/ppc64/lparcfg Anton Blanchard
2013-12-12 4:59 ` [PATCH 5/8] powerpc/pseries: Fix endian issues in nvram code Anton Blanchard
2013-12-12 4:59 ` [PATCH 6/8] powerpc/pseries: Fix PCIE link speed endian issue Anton Blanchard
2013-12-12 4:59 ` [PATCH 7/8] powerpc/pseries: Fix endian issues in MSI code Anton Blanchard
2013-12-12 4:59 ` [PATCH 8/8] powerpc: Fix endian issues in crash dump code Anton Blanchard
2013-12-18 4:45 ` Michael Ellerman
2014-01-22 10:42 ` Anton Blanchard
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