Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S965113AbcJ2Nux (ORCPT ); Sat, 29 Oct 2016 09:50:53 -0400 Received: from mail.linuxfoundation.org ([140.211.169.12]:49174 "EHLO mail.linuxfoundation.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S938493AbcJ2Nuj (ORCPT ); Sat, 29 Oct 2016 09:50:39 -0400 From: Greg Kroah-Hartman To: linux-kernel@vger.kernel.org Cc: Greg Kroah-Hartman , stable@vger.kernel.org, Sebastian Ott , Peter Oberparleiter , Martin Schwidefsky Subject: [PATCH 4.4 41/51] s390/cio: fix accidental interrupt enabling during resume Date: Sat, 29 Oct 2016 09:49:42 -0400 Message-Id: <20161029134924.252142403@linuxfoundation.org> X-Mailer: git-send-email 2.10.1 In-Reply-To: <20161029134922.501052551@linuxfoundation.org> References: <20161029134922.501052551@linuxfoundation.org> User-Agent: quilt/0.64 MIME-Version: 1.0 Content-Type: text/plain; charset=UTF-8 Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Content-Length: 3878 Lines: 127 4.4-stable review patch. If anyone has any objections, please let me know. ------------------ From: Sebastian Ott commit d53c51f26145657aa7c55fa396f93677e613548d upstream. Since commit 9f3d6d7 chsc_get_channel_measurement_chars is called with interrupts disabled during resume from hibernate. Since this function used spin_unlock_irq, interrupts have been enabled accidentally. Fix this by using the irqsave variant. Since we can't guarantee the IRQ-enablement state for all (future/ external) callers, change the locking in related functions to prevent similar bugs in the future. Fixes: 9f3d6d7 ("s390/cio: update measurement characteristics") Signed-off-by: Sebastian Ott Reviewed-by: Peter Oberparleiter Signed-off-by: Martin Schwidefsky Signed-off-by: Greg Kroah-Hartman --- drivers/s390/cio/chsc.c | 20 ++++++++++++-------- 1 file changed, 12 insertions(+), 8 deletions(-) --- a/drivers/s390/cio/chsc.c +++ b/drivers/s390/cio/chsc.c @@ -95,12 +95,13 @@ struct chsc_ssd_area { int chsc_get_ssd_info(struct subchannel_id schid, struct chsc_ssd_info *ssd) { struct chsc_ssd_area *ssd_area; + unsigned long flags; int ccode; int ret; int i; int mask; - spin_lock_irq(&chsc_page_lock); + spin_lock_irqsave(&chsc_page_lock, flags); memset(chsc_page, 0, PAGE_SIZE); ssd_area = chsc_page; ssd_area->request.length = 0x0010; @@ -144,7 +145,7 @@ int chsc_get_ssd_info(struct subchannel_ ssd->fla[i] = ssd_area->fla[i]; } out: - spin_unlock_irq(&chsc_page_lock); + spin_unlock_irqrestore(&chsc_page_lock, flags); return ret; } @@ -832,9 +833,10 @@ int __chsc_do_secm(struct channel_subsys u32 fmt : 4; u32 : 16; } __attribute__ ((packed)) *secm_area; + unsigned long flags; int ret, ccode; - spin_lock_irq(&chsc_page_lock); + spin_lock_irqsave(&chsc_page_lock, flags); memset(chsc_page, 0, PAGE_SIZE); secm_area = chsc_page; secm_area->request.length = 0x0050; @@ -864,7 +866,7 @@ int __chsc_do_secm(struct channel_subsys CIO_CRW_EVENT(2, "chsc: secm failed (rc=%04x)\n", secm_area->response.code); out: - spin_unlock_irq(&chsc_page_lock); + spin_unlock_irqrestore(&chsc_page_lock, flags); return ret; } @@ -993,6 +995,7 @@ chsc_initialize_cmg_chars(struct channel int chsc_get_channel_measurement_chars(struct channel_path *chp) { + unsigned long flags; int ccode, ret; struct { @@ -1022,7 +1025,7 @@ int chsc_get_channel_measurement_chars(s if (!css_chsc_characteristics.scmc || !css_chsc_characteristics.secm) return 0; - spin_lock_irq(&chsc_page_lock); + spin_lock_irqsave(&chsc_page_lock, flags); memset(chsc_page, 0, PAGE_SIZE); scmc_area = chsc_page; scmc_area->request.length = 0x0010; @@ -1054,7 +1057,7 @@ int chsc_get_channel_measurement_chars(s chsc_initialize_cmg_chars(chp, scmc_area->cmcv, (struct cmg_chars *) &scmc_area->data); out: - spin_unlock_irq(&chsc_page_lock); + spin_unlock_irqrestore(&chsc_page_lock, flags); return ret; } @@ -1135,6 +1138,7 @@ struct css_chsc_char css_chsc_characteri int __init chsc_determine_css_characteristics(void) { + unsigned long flags; int result; struct { struct chsc_header request; @@ -1147,7 +1151,7 @@ chsc_determine_css_characteristics(void) u32 chsc_char[508]; } __attribute__ ((packed)) *scsc_area; - spin_lock_irq(&chsc_page_lock); + spin_lock_irqsave(&chsc_page_lock, flags); memset(chsc_page, 0, PAGE_SIZE); scsc_area = chsc_page; scsc_area->request.length = 0x0010; @@ -1169,7 +1173,7 @@ chsc_determine_css_characteristics(void) CIO_CRW_EVENT(2, "chsc: scsc failed (rc=%04x)\n", scsc_area->response.code); exit: - spin_unlock_irq(&chsc_page_lock); + spin_unlock_irqrestore(&chsc_page_lock, flags); return result; }