From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: from mail.linuxfoundation.org ([140.211.169.12]:60956 "EHLO mail.linuxfoundation.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1751201AbcFDSlH (ORCPT ); Sat, 4 Jun 2016 14:41:07 -0400 Subject: Patch "MIPS: Disable preemption during prctl(PR_SET_FP_MODE, ...)" has been added to the 4.5-stable tree To: paul.burton@imgtec.com, adam.buchbinder@gmail.com, aurelien@aurel32.net, gregkh@linuxfoundation.org, james.hogan@imgtec.com, macro@imgtec.com, ralf@linux-mips.org Cc: , From: Date: Sat, 04 Jun 2016 11:41:06 -0700 Message-ID: <146506566680112@kroah.com> MIME-Version: 1.0 Content-Type: text/plain; charset=ANSI_X3.4-1968 Content-Transfer-Encoding: 8bit Sender: stable-owner@vger.kernel.org List-ID: This is a note to let you know that I've just added the patch titled MIPS: Disable preemption during prctl(PR_SET_FP_MODE, ...) to the 4.5-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: mips-disable-preemption-during-prctl-pr_set_fp_mode.patch and it can be found in the queue-4.5 subdirectory. If you, or anyone else, feels it should not be added to the stable tree, please let know about it. >>From bd239f1e1429e7781096bf3884bdb1b2b1bb4f28 Mon Sep 17 00:00:00 2001 From: Paul Burton Date: Thu, 21 Apr 2016 12:43:57 +0100 Subject: MIPS: Disable preemption during prctl(PR_SET_FP_MODE, ...) From: Paul Burton commit bd239f1e1429e7781096bf3884bdb1b2b1bb4f28 upstream. Whilst a PR_SET_FP_MODE prctl is performed there are decisions made based upon whether the task is executing on the current CPU. This may change if we're preempted, so disable preemption to avoid such changes for the lifetime of the mode switch. Signed-off-by: Paul Burton Fixes: 9791554b45a2 ("MIPS,prctl: add PR_[GS]ET_FP_MODE prctl options for MIPS") Reviewed-by: Maciej W. Rozycki Tested-by: Aurelien Jarno Cc: Adam Buchbinder Cc: James Hogan Cc: linux-mips@linux-mips.org Cc: linux-kernel@vger.kernel.org Patchwork: https://patchwork.linux-mips.org/patch/13144/ Signed-off-by: Ralf Baechle Signed-off-by: Greg Kroah-Hartman --- arch/mips/kernel/process.c | 4 ++++ 1 file changed, 4 insertions(+) --- a/arch/mips/kernel/process.c +++ b/arch/mips/kernel/process.c @@ -601,6 +601,9 @@ int mips_set_process_fp_mode(struct task if (!(value & PR_FP_MODE_FR) && cpu_has_fpu && cpu_has_mips_r6) return -EOPNOTSUPP; + /* Proceed with the mode switch */ + preempt_disable(); + /* Save FP & vector context, then disable FPU & MSA */ if (task->signal == current->signal) lose_fpu(1); @@ -659,6 +662,7 @@ int mips_set_process_fp_mode(struct task /* Allow threads to use FP again */ atomic_set(&task->mm->context.fp_mode_switching, 0); + preempt_enable(); return 0; } Patches currently in stable-queue which might be from paul.burton@imgtec.com are queue-4.5/mips-disable-preemption-during-prctl-pr_set_fp_mode.patch queue-4.5/mips-fix-sigreturn-via-vdso-on-micromips-kernel.patch queue-4.5/mips-handle-highmem-pages-in-__update_cache.patch queue-4.5/mips-fix-watchpoint-restoration.patch queue-4.5/mips-build-micromips-vdso-for-micromips-kernels.patch queue-4.5/mips-math-emu-fix-jalr-emulation-when-rd-0.patch queue-4.5/mips-sync-icache-dcache-in-set_pte_at.patch queue-4.5/mips-fix-msa-ld_-st_-asm-macros-to-use-ptr_addu.patch queue-4.5/mips-prevent-restoration-of-msa-context-in-non-msa-kernels.patch queue-4.5/mips-use-copy_s.fmt-rather-than-copy_u.fmt.patch