From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: X-Spam-Checker-Version: SpamAssassin 3.4.0 (2014-02-07) on aws-us-west-2-korg-lkml-1.web.codeaurora.org X-Spam-Level: X-Spam-Status: No, score=-8.5 required=3.0 tests=HEADER_FROM_DIFFERENT_DOMAINS, INCLUDES_PATCH,MAILING_LIST_MULTI,SIGNED_OFF_BY,SPF_PASS,URIBL_BLOCKED, USER_AGENT_MUTT autolearn=ham autolearn_force=no version=3.4.0 Received: from mail.kernel.org (mail.kernel.org [198.145.29.99]) by smtp.lore.kernel.org (Postfix) with ESMTP id 0E78BC282C2 for ; Thu, 7 Feb 2019 17:38:41 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.kernel.org (Postfix) with ESMTP id C68BA21721 for ; Thu, 7 Feb 2019 17:38:40 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1726858AbfBGRij (ORCPT ); Thu, 7 Feb 2019 12:38:39 -0500 Received: from mx0b-002e3701.pphosted.com ([148.163.143.35]:49318 "EHLO mx0b-002e3701.pphosted.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1726319AbfBGRii (ORCPT ); Thu, 7 Feb 2019 12:38:38 -0500 Received: from pps.filterd (m0150244.ppops.net [127.0.0.1]) by mx0b-002e3701.pphosted.com (8.16.0.27/8.16.0.27) with SMTP id x17HZjuU032723; Thu, 7 Feb 2019 17:38:15 GMT Received: from g9t5008.houston.hpe.com (g9t5008.houston.hpe.com [15.241.48.72]) by mx0b-002e3701.pphosted.com with ESMTP id 2qgq3eh9jn-1 (version=TLSv1.2 cipher=ECDHE-RSA-AES256-GCM-SHA384 bits=256 verify=NOT); Thu, 07 Feb 2019 17:38:15 +0000 Received: from sarge.linuxathome.me (unknown [16.99.168.108]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by g9t5008.houston.hpe.com (Postfix) with ESMTPS id 24BC757; Thu, 7 Feb 2019 17:38:11 +0000 (UTC) Date: Thu, 7 Feb 2019 17:38:08 +0000 From: Hedi Berriche To: Ard Biesheuvel Cc: Linux Kernel Mailing List , Thomas Gleixner , Bhupesh Sharma , Ingo Molnar , Borislav Petkov , "H. Peter Anvin" , linux-efi , the arch/x86 maintainers , Russ Anderson , Mike Travis , Dimitri Sivanich , Steve Wahl , stable Subject: Re: [Patch v2 1/4] efi/x86: turn EFI runtime semaphore into a global lock Message-ID: <20190207173808.GE6398@sarge.linuxathome.me> Mail-Followup-To: Ard Biesheuvel , Linux Kernel Mailing List , Thomas Gleixner , Bhupesh Sharma , Ingo Molnar , Borislav Petkov , "H. Peter Anvin" , linux-efi , the arch/x86 maintainers , Russ Anderson , Mike Travis , Dimitri Sivanich , Steve Wahl , stable References: <20190207042234.25109-1-hedi.berriche@hpe.com> <20190207042234.25109-2-hedi.berriche@hpe.com> MIME-Version: 1.0 Content-Type: text/plain; charset=utf-8; format=flowed Content-Disposition: inline In-Reply-To: User-Agent: Mutt/1.10.1 (2018-07-13) X-HPE-SCL: -1 X-Proofpoint-Virus-Version: vendor=fsecure engine=2.50.10434:,, definitions=2019-02-07_11:,, signatures=0 X-Proofpoint-Spam-Details: rule=outbound_notspam policy=outbound score=0 priorityscore=1501 malwarescore=0 suspectscore=0 phishscore=0 bulkscore=0 spamscore=0 clxscore=1015 lowpriorityscore=0 mlxscore=0 impostorscore=0 mlxlogscore=999 adultscore=0 classifier=spam adjust=0 reason=mlx scancount=1 engine=8.0.1-1810050000 definitions=main-1902070133 Sender: linux-kernel-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org On Thu, Feb 07, 2019 at 16:05 Ard Biesheuvel wrote: >On Thu, 7 Feb 2019 at 05:23, Hedi Berriche wrote: >> >> Make efi_runtime_lock semaphore global so that it can be used by EFI >> runtime callers that may be defined outside efi/runtime-wrappers.c. >> >> Also now that efi_runtime_lock semaphore is no longer static, rename it >> to efi_runtime_sem so it doesn't clash with the efi_runtime_lock spinlock >> defined in arch/x86/platform/efi/efi_64.c when CONFIG_EFI_MIXED is >> enabled. >> >> The immediate motivation of this change is to serialise UV platform BIOS >> calls using the efi_runtime_sem semaphore. >> >> No functional changes. >> >> Cc: Russ Anderson >> Cc: Mike Travis >> Cc: Dimitri Sivanich >> Cc: Steve Wahl >> Cc: stable@vger.kernel.org >> Signed-off-by: Hedi Berriche > >Hello Hedi, Hi Ard, >Same feedback as on v1: please don't rename the lock. With the efi_runtime_lock semaphore being no longer static, not renaming it will cause a compile failure as it will clash with the declaration of the efi_runtime_lock *spinlock* in arch/x86/platform/efi/efi_64.c in the CONFIG_EFI_MIXED case. >> --- >> drivers/firmware/efi/runtime-wrappers.c | 60 ++++++++++++------------- >> include/linux/efi.h | 3 ++ >> 2 files changed, 33 insertions(+), 30 deletions(-) >> >> diff --git a/drivers/firmware/efi/runtime-wrappers.c b/drivers/firmware/efi/runtime-wrappers.c >> index 8903b9ccfc2b..ec60d6227925 100644 >> --- a/drivers/firmware/efi/runtime-wrappers.c >> +++ b/drivers/firmware/efi/runtime-wrappers.c >> @@ -53,7 +53,7 @@ struct efi_runtime_work efi_rts_work; >> * @rts_arg<1-5>: efi_runtime_service() function arguments >> * >> * Accesses to efi_runtime_services() are serialized by a binary >> - * semaphore (efi_runtime_lock) and caller waits until the work is >> + * semaphore (efi_runtime_sem) and caller waits until the work is >> * finished, hence _only_ one work is queued at a time and the caller >> * thread waits for completion. >> */ >> @@ -144,7 +144,7 @@ void efi_call_virt_check_flags(unsigned long flags, const char *call) >> * none of the remaining functions are actually ever called at runtime. >> * So let's just use a single lock to serialize all Runtime Services calls. >> */ >> -static DEFINE_SEMAPHORE(efi_runtime_lock); >> +DEFINE_SEMAPHORE(efi_runtime_sem); >> >> /* >> * Calls the appropriate efi_runtime_service() with the appropriate >> @@ -233,10 +233,10 @@ static efi_status_t virt_efi_get_time(efi_time_t *tm, efi_time_cap_t *tc) >> { >> efi_status_t status; >> >> - if (down_interruptible(&efi_runtime_lock)) >> + if (down_interruptible(&efi_runtime_sem)) >> return EFI_ABORTED; >> status = efi_queue_work(GET_TIME, tm, tc, NULL, NULL, NULL); >> - up(&efi_runtime_lock); >> + up(&efi_runtime_sem); >> return status; >> } >> >> @@ -244,10 +244,10 @@ static efi_status_t virt_efi_set_time(efi_time_t *tm) >> { >> efi_status_t status; >> >> - if (down_interruptible(&efi_runtime_lock)) >> + if (down_interruptible(&efi_runtime_sem)) >> return EFI_ABORTED; >> status = efi_queue_work(SET_TIME, tm, NULL, NULL, NULL, NULL); >> - up(&efi_runtime_lock); >> + up(&efi_runtime_sem); >> return status; >> } >> >> @@ -257,11 +257,11 @@ static efi_status_t virt_efi_get_wakeup_time(efi_bool_t *enabled, >> { >> efi_status_t status; >> >> - if (down_interruptible(&efi_runtime_lock)) >> + if (down_interruptible(&efi_runtime_sem)) >> return EFI_ABORTED; >> status = efi_queue_work(GET_WAKEUP_TIME, enabled, pending, tm, NULL, >> NULL); >> - up(&efi_runtime_lock); >> + up(&efi_runtime_sem); >> return status; >> } >> >> @@ -269,11 +269,11 @@ static efi_status_t virt_efi_set_wakeup_time(efi_bool_t enabled, efi_time_t *tm) >> { >> efi_status_t status; >> >> - if (down_interruptible(&efi_runtime_lock)) >> + if (down_interruptible(&efi_runtime_sem)) >> return EFI_ABORTED; >> status = efi_queue_work(SET_WAKEUP_TIME, &enabled, tm, NULL, NULL, >> NULL); >> - up(&efi_runtime_lock); >> + up(&efi_runtime_sem); >> return status; >> } >> >> @@ -285,11 +285,11 @@ static efi_status_t virt_efi_get_variable(efi_char16_t *name, >> { >> efi_status_t status; >> >> - if (down_interruptible(&efi_runtime_lock)) >> + if (down_interruptible(&efi_runtime_sem)) >> return EFI_ABORTED; >> status = efi_queue_work(GET_VARIABLE, name, vendor, attr, data_size, >> data); >> - up(&efi_runtime_lock); >> + up(&efi_runtime_sem); >> return status; >> } >> >> @@ -299,11 +299,11 @@ static efi_status_t virt_efi_get_next_variable(unsigned long *name_size, >> { >> efi_status_t status; >> >> - if (down_interruptible(&efi_runtime_lock)) >> + if (down_interruptible(&efi_runtime_sem)) >> return EFI_ABORTED; >> status = efi_queue_work(GET_NEXT_VARIABLE, name_size, name, vendor, >> NULL, NULL); >> - up(&efi_runtime_lock); >> + up(&efi_runtime_sem); >> return status; >> } >> >> @@ -315,11 +315,11 @@ static efi_status_t virt_efi_set_variable(efi_char16_t *name, >> { >> efi_status_t status; >> >> - if (down_interruptible(&efi_runtime_lock)) >> + if (down_interruptible(&efi_runtime_sem)) >> return EFI_ABORTED; >> status = efi_queue_work(SET_VARIABLE, name, vendor, &attr, &data_size, >> data); >> - up(&efi_runtime_lock); >> + up(&efi_runtime_sem); >> return status; >> } >> >> @@ -330,12 +330,12 @@ virt_efi_set_variable_nonblocking(efi_char16_t *name, efi_guid_t *vendor, >> { >> efi_status_t status; >> >> - if (down_trylock(&efi_runtime_lock)) >> + if (down_trylock(&efi_runtime_sem)) >> return EFI_NOT_READY; >> >> status = efi_call_virt(set_variable, name, vendor, attr, data_size, >> data); >> - up(&efi_runtime_lock); >> + up(&efi_runtime_sem); >> return status; >> } >> >> @@ -350,11 +350,11 @@ static efi_status_t virt_efi_query_variable_info(u32 attr, >> if (efi.runtime_version < EFI_2_00_SYSTEM_TABLE_REVISION) >> return EFI_UNSUPPORTED; >> >> - if (down_interruptible(&efi_runtime_lock)) >> + if (down_interruptible(&efi_runtime_sem)) >> return EFI_ABORTED; >> status = efi_queue_work(QUERY_VARIABLE_INFO, &attr, storage_space, >> remaining_space, max_variable_size, NULL); >> - up(&efi_runtime_lock); >> + up(&efi_runtime_sem); >> return status; >> } >> >> @@ -369,12 +369,12 @@ virt_efi_query_variable_info_nonblocking(u32 attr, >> if (efi.runtime_version < EFI_2_00_SYSTEM_TABLE_REVISION) >> return EFI_UNSUPPORTED; >> >> - if (down_trylock(&efi_runtime_lock)) >> + if (down_trylock(&efi_runtime_sem)) >> return EFI_NOT_READY; >> >> status = efi_call_virt(query_variable_info, attr, storage_space, >> remaining_space, max_variable_size); >> - up(&efi_runtime_lock); >> + up(&efi_runtime_sem); >> return status; >> } >> >> @@ -382,11 +382,11 @@ static efi_status_t virt_efi_get_next_high_mono_count(u32 *count) >> { >> efi_status_t status; >> >> - if (down_interruptible(&efi_runtime_lock)) >> + if (down_interruptible(&efi_runtime_sem)) >> return EFI_ABORTED; >> status = efi_queue_work(GET_NEXT_HIGH_MONO_COUNT, count, NULL, NULL, >> NULL, NULL); >> - up(&efi_runtime_lock); >> + up(&efi_runtime_sem); >> return status; >> } >> >> @@ -395,14 +395,14 @@ static void virt_efi_reset_system(int reset_type, >> unsigned long data_size, >> efi_char16_t *data) >> { >> - if (down_interruptible(&efi_runtime_lock)) { >> + if (down_interruptible(&efi_runtime_sem)) { >> pr_warn("failed to invoke the reset_system() runtime service:\n" >> "could not get exclusive access to the firmware\n"); >> return; >> } >> efi_rts_work.efi_rts_id = RESET_SYSTEM; >> __efi_call_virt(reset_system, reset_type, status, data_size, data); >> - up(&efi_runtime_lock); >> + up(&efi_runtime_sem); >> } >> >> static efi_status_t virt_efi_update_capsule(efi_capsule_header_t **capsules, >> @@ -414,11 +414,11 @@ static efi_status_t virt_efi_update_capsule(efi_capsule_header_t **capsules, >> if (efi.runtime_version < EFI_2_00_SYSTEM_TABLE_REVISION) >> return EFI_UNSUPPORTED; >> >> - if (down_interruptible(&efi_runtime_lock)) >> + if (down_interruptible(&efi_runtime_sem)) >> return EFI_ABORTED; >> status = efi_queue_work(UPDATE_CAPSULE, capsules, &count, &sg_list, >> NULL, NULL); >> - up(&efi_runtime_lock); >> + up(&efi_runtime_sem); >> return status; >> } >> >> @@ -432,11 +432,11 @@ static efi_status_t virt_efi_query_capsule_caps(efi_capsule_header_t **capsules, >> if (efi.runtime_version < EFI_2_00_SYSTEM_TABLE_REVISION) >> return EFI_UNSUPPORTED; >> >> - if (down_interruptible(&efi_runtime_lock)) >> + if (down_interruptible(&efi_runtime_sem)) >> return EFI_ABORTED; >> status = efi_queue_work(QUERY_CAPSULE_CAPS, capsules, &count, >> max_size, reset_type, NULL); >> - up(&efi_runtime_lock); >> + up(&efi_runtime_sem); >> return status; >> } >> >> diff --git a/include/linux/efi.h b/include/linux/efi.h >> index 45ff763fba76..930cd20842b8 100644 >> --- a/include/linux/efi.h >> +++ b/include/linux/efi.h >> @@ -1745,6 +1745,9 @@ extern struct efi_runtime_work efi_rts_work; >> /* Workqueue to queue EFI Runtime Services */ >> extern struct workqueue_struct *efi_rts_wq; >> >> +/* EFI runtime semaphore */ >> +extern struct semaphore efi_runtime_sem; >> + >> struct linux_efi_memreserve { >> int size; // allocated size of the array >> atomic_t count; // number of entries used >> -- >> 2.20.1 >> -- Be careful of reading health books, you might die of a misprint. -- Mark Twain