From: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
To: linux-kernel@vger.kernel.org
Cc: Greg Kroah-Hartman <gregkh@linuxfoundation.org>,
stable@vger.kernel.org, Alex Smith <alex@alex-smith.me.uk>,
linux-mips@linux-mips.org, Ralf Baechle <ralf@linux-mips.org>
Subject: [PATCH 3.16 064/158] MIPS: ptrace: Avoid smp_processor_id() when retrieving FPU IR
Date: Mon, 15 Sep 2014 12:25:03 -0700 [thread overview]
Message-ID: <20140915192544.816172080@linuxfoundation.org> (raw)
In-Reply-To: <20140915192542.872134685@linuxfoundation.org>
3.16-stable review patch. If anyone has any objections, please let me know.
------------------
From: Alex Smith <alex@alex-smith.me.uk>
commit 656ff9bef08c19a6471b49528dacb4cbbeb1e537 upstream.
Whenever ptrace attempts to retrieve the FPU implementation register it
accesses it through current_cpu_data, which calls smp_processor_id().
Since the code may execute with preemption enabled, this can trigger
a warning. Fix this by using boot_cpu_data to get the IR instead.
Signed-off-by: Alex Smith <alex@alex-smith.me.uk>
Cc: linux-mips@linux-mips.org
Patchwork: https://patchwork.linux-mips.org/patch/7449/
Signed-off-by: Ralf Baechle <ralf@linux-mips.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
---
arch/mips/kernel/ptrace.c | 4 ++--
arch/mips/kernel/ptrace32.c | 2 +-
2 files changed, 3 insertions(+), 3 deletions(-)
--- a/arch/mips/kernel/ptrace.c
+++ b/arch/mips/kernel/ptrace.c
@@ -129,7 +129,7 @@ int ptrace_getfpregs(struct task_struct
}
__put_user(child->thread.fpu.fcr31, data + 64);
- __put_user(current_cpu_data.fpu_id, data + 65);
+ __put_user(boot_cpu_data.fpu_id, data + 65);
return 0;
}
@@ -611,7 +611,7 @@ long arch_ptrace(struct task_struct *chi
break;
case FPC_EIR:
/* implementation / version register */
- tmp = current_cpu_data.fpu_id;
+ tmp = boot_cpu_data.fpu_id;
break;
case DSP_BASE ... DSP_BASE + 5: {
dspreg_t *dregs;
--- a/arch/mips/kernel/ptrace32.c
+++ b/arch/mips/kernel/ptrace32.c
@@ -129,7 +129,7 @@ long compat_arch_ptrace(struct task_stru
break;
case FPC_EIR:
/* implementation / version register */
- tmp = current_cpu_data.fpu_id;
+ tmp = boot_cpu_data.fpu_id;
break;
case DSP_BASE ... DSP_BASE + 5: {
dspreg_t *dregs;
next prev parent reply other threads:[~2014-09-15 19:29 UTC|newest]
Thread overview: 11+ messages / expand[flat|nested] mbox.gz Atom feed top
[not found] <20140915192542.872134685@linuxfoundation.org>
2014-09-15 19:24 ` [PATCH 3.16 060/158] MIPS: GIC: Prevent array overrun Greg Kroah-Hartman
2014-09-15 19:25 ` [PATCH 3.16 061/158] MIPS: O32/32-bit: Fix bug which can cause incorrect system call restarts Greg Kroah-Hartman
2014-09-15 19:25 ` [PATCH 3.16 062/158] MIPS: ptrace: Test correct tasks flags in task_user_regset_view() Greg Kroah-Hartman
2014-09-15 19:25 ` [PATCH 3.16 063/158] MIPS: ptrace: Change GP regset to use correct core dump register layout Greg Kroah-Hartman
2014-09-15 19:25 ` Greg Kroah-Hartman [this message]
2014-09-15 19:25 ` [PATCH 3.16 065/158] MIPS: smp-mt: Fix link error when PROC_FS=n Greg Kroah-Hartman
2014-09-15 19:25 ` [PATCH 3.16 066/158] MIPS: Prevent user from setting FCSR cause bits Greg Kroah-Hartman
2014-09-15 19:25 ` [PATCH 3.16 067/158] MIPS: tlbex: Fix a missing statement for HUGETLB Greg Kroah-Hartman
2014-09-15 19:25 ` [PATCH 3.16 068/158] MIPS: Remove BUG_ON(!is_fpu_owner()) in do_ade() Greg Kroah-Hartman
2014-09-15 19:25 ` [PATCH 3.16 069/158] MIPS: asm/reg.h: Make 32- and 64-bit definitions available at the same time Greg Kroah-Hartman
2014-09-15 19:25 ` [PATCH 3.16 072/158] MIPS: Malta: Improve system memory detection for {e, }memsize >= 2G Greg Kroah-Hartman
Reply instructions:
You may reply publicly to this message via plain-text email
using any one of the following methods:
* Save the following mbox file, import it into your mail client,
and reply-to-all from there: mbox
Avoid top-posting and favor interleaved quoting:
https://en.wikipedia.org/wiki/Posting_style#Interleaved_style
* Reply using the --to, --cc, and --in-reply-to
switches of git-send-email(1):
git send-email \
--in-reply-to=20140915192544.816172080@linuxfoundation.org \
--to=gregkh@linuxfoundation.org \
--cc=alex@alex-smith.me.uk \
--cc=linux-kernel@vger.kernel.org \
--cc=linux-mips@linux-mips.org \
--cc=ralf@linux-mips.org \
--cc=stable@vger.kernel.org \
/path/to/YOUR_REPLY
https://kernel.org/pub/software/scm/git/docs/git-send-email.html
* If your mail client supports setting the In-Reply-To header
via mailto: links, try the mailto: link
Be sure your reply has a Subject: header at the top and a blank line
before the message body.
This is a public inbox, see mirroring instructions
for how to clone and mirror all data and code used for this inbox