From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: from mail.linuxfoundation.org ([140.211.169.12]:48536 "EHLO mail.linuxfoundation.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1756385AbcJ2NUl (ORCPT ); Sat, 29 Oct 2016 09:20:41 -0400 Subject: Patch "powerpc: Add check_if_tm_restore_required() to giveup_all()" has been added to the 4.8-stable tree To: cyrilbur@gmail.com, gregkh@linuxfoundation.org, mpe@ellerman.id.au Cc: , From: Date: Sat, 29 Oct 2016 09:20:25 -0400 Message-ID: <1477747225195174@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 powerpc: Add check_if_tm_restore_required() to giveup_all() to the 4.8-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: powerpc-add-check_if_tm_restore_required-to-giveup_all.patch and it can be found in the queue-4.8 subdirectory. If you, or anyone else, feels it should not be added to the stable tree, please let know about it. >>From b0f16b46988fde02a1e32078f66a3059d7e53bfc Mon Sep 17 00:00:00 2001 From: Cyril Bur Date: Fri, 23 Sep 2016 16:18:09 +1000 Subject: powerpc: Add check_if_tm_restore_required() to giveup_all() From: Cyril Bur commit b0f16b46988fde02a1e32078f66a3059d7e53bfc upstream. giveup_all() causes FPU/VMX/VSX facilities to be disabled in a threads MSR. If the thread performing the giveup was transactional, the kernel must record which facilities were in use before the giveup as the thread must have these facilities re-enabled on return to userspace. >>>From process.c: /* * This is called if we are on the way out to userspace and the * TIF_RESTORE_TM flag is set. It checks if we need to reload * FP and/or vector state and does so if necessary. * If userspace is inside a transaction (whether active or * suspended) and FP/VMX/VSX instructions have ever been enabled * inside that transaction, then we have to keep them enabled * and keep the FP/VMX/VSX state loaded while ever the transaction * continues. The reason is that if we didn't, and subsequently * got a FP/VMX/VSX unavailable interrupt inside a transaction, * we don't know whether it's the same transaction, and thus we * don't know which of the checkpointed state and the transactional * state to use. */ Calling check_if_tm_restore_required() will set TIF_RESTORE_TM and save the MSR if needed. Fixes: c208505 ("powerpc: create giveup_all()") Signed-off-by: Cyril Bur Signed-off-by: Michael Ellerman Signed-off-by: Greg Kroah-Hartman --- arch/powerpc/kernel/process.c | 1 + 1 file changed, 1 insertion(+) --- a/arch/powerpc/kernel/process.c +++ b/arch/powerpc/kernel/process.c @@ -445,6 +445,7 @@ void giveup_all(struct task_struct *tsk) return; msr_check_and_set(msr_all_available); + check_if_tm_restore_required(tsk); #ifdef CONFIG_PPC_FPU if (usermsr & MSR_FP) Patches currently in stable-queue which might be from cyrilbur@gmail.com are queue-4.8/powerpc-add-check_if_tm_restore_required-to-giveup_all.patch queue-4.8/powerpc-always-restore-fpu-vec-vsx-if-hardware-transactional-memory-in-use.patch