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=-8.8 required=3.0 tests=DKIM_SIGNED,DKIM_VALID, DKIM_VALID_AU,HEADER_FROM_DIFFERENT_DOMAINS,INCLUDES_PATCH,MAILING_LIST_MULTI, SIGNED_OFF_BY,SPF_PASS,URIBL_BLOCKED,USER_AGENT_GIT 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 6ED1EC43382 for ; Thu, 27 Sep 2018 08:51:44 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.kernel.org (Postfix) with ESMTP id 155BD21570 for ; Thu, 27 Sep 2018 08:51:44 +0000 (UTC) Authentication-Results: mail.kernel.org; dkim=pass (1024-bit key) header.d=linaro.org header.i=@linaro.org header.b="CTudQxlz" DMARC-Filter: OpenDMARC Filter v1.3.2 mail.kernel.org 155BD21570 Authentication-Results: mail.kernel.org; dmarc=fail (p=none dis=none) header.from=linaro.org Authentication-Results: mail.kernel.org; spf=none smtp.mailfrom=linux-kernel-owner@vger.kernel.org Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1727410AbeI0PIR (ORCPT ); Thu, 27 Sep 2018 11:08:17 -0400 Received: from mail-wr1-f67.google.com ([209.85.221.67]:38781 "EHLO mail-wr1-f67.google.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1727362AbeI0PIP (ORCPT ); Thu, 27 Sep 2018 11:08:15 -0400 Received: by mail-wr1-f67.google.com with SMTP id j8-v6so1663574wrw.5 for ; Thu, 27 Sep 2018 01:51:05 -0700 (PDT) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=linaro.org; s=google; h=from:to:cc:subject:date:message-id:in-reply-to:references; bh=8qG3i7EOfW75+1ul/qMJed+W8vBlnWG4DFjga9+cTRI=; b=CTudQxlzyl1XsS+Y4b5DeSKYBr5h0qMtnEAEWbqW3aHZsDDutmDbVGk0frhXrwe1Ia zQJEgZvV7TL7KSq/VgT14zQFbM8tni0q3Ku3OI9UkL/bkiNtWpdDyfptBlFFVMHn+W26 VwtF2/bUqNkonFF2yk7reykD+QR+JdIDlqXjo= X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20161025; h=x-gm-message-state:from:to:cc:subject:date:message-id:in-reply-to :references; bh=8qG3i7EOfW75+1ul/qMJed+W8vBlnWG4DFjga9+cTRI=; b=NC44PWp+5TPfeHrnClip6UqB3+yOtBVRDEifSinNwLiOn2XA8pgV4smS7vEK6XvcQX cF37CCNzqUrvBxum3Q3ggkCpk1YDDVvSqgZ37QnudHPavipCFMdmEWmqx4YQzqx16MsU +CtLbAG6rzI7jojfiVD6pkbktaTSlmk1gWtHEonkb1HlSMlO0QxYrj3hd5RIqKdSGbb1 sxf63EWmsYB9aaM8lAk5fpoqdKpjr+KK+rd9BpBiTAaXdGExjdBXsHtjtaomn3SWWBVt 4kQ4XnSD3LKPj84JkexAI4WTjxnqbOzLZQ8XR4zNRen2Tv07mLYNt1xKsq7DuWFo0og6 TTUA== X-Gm-Message-State: ABuFfogMIePGbzq6zTNsK8pSQnnHR2/9rF7YZN5U2ywdnS4eSXFrrbVi oPHoyWIrFuZxf8dNHVifXhqNgXoB0ok= X-Google-Smtp-Source: ACcGV62Mb11ea8WdxnDlE9pZA3dzvfHLsyT5g8SgZ5Z7kXtGNkQZTod3aYHL4ZgzZmPtqzaNfECktg== X-Received: by 2002:adf:fb0e:: with SMTP id c14-v6mr7970479wrr.117.1538038264841; Thu, 27 Sep 2018 01:51:04 -0700 (PDT) Received: from rev03.home ([2a01:cb1d:112:6f00:546e:3c44:5966:2f5e]) by smtp.gmail.com with ESMTPSA id p11-v6sm1304055wrd.74.2018.09.27.01.51.03 (version=TLS1_2 cipher=ECDHE-RSA-AES128-GCM-SHA256 bits=128/128); Thu, 27 Sep 2018 01:51:04 -0700 (PDT) From: Ard Biesheuvel To: linux-kernel@vger.kernel.org, Ingo Molnar , Thomas Gleixner Cc: Ard Biesheuvel , linux-efi@vger.kernel.org, Aaron Ma , Alistair Strachan , Ben Hutchings , Bhupesh Sharma , Hans de Goede , Ivan Hu , Jeremy Linton , Marc Zyngier , Matt Fleming , Peter Robinson , Sai Praneeth Prakhya , Sebastian Andrzej Siewior , Stefan Agner Subject: [PATCH 06/11] efi: Make efi_rts_work accessible to efi page fault handler Date: Thu, 27 Sep 2018 10:50:33 +0200 Message-Id: <20180927085039.8391-7-ard.biesheuvel@linaro.org> X-Mailer: git-send-email 2.18.0 In-Reply-To: <20180927085039.8391-1-ard.biesheuvel@linaro.org> References: <20180927085039.8391-1-ard.biesheuvel@linaro.org> Sender: linux-kernel-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org From: Sai Praneeth After the kernel has booted, if any accesses by firmware causes a page fault, the efi page fault handler would freeze efi_rts_wq and schedules a new process. To do this, the efi page fault handler needs efi_rts_work. Hence, make it accessible. There will be no race conditions in accessing this structure, because all the calls to efi runtime services are already serialized. Tested-by: Bhupesh Sharma Suggested-by: Matt Fleming Based-on-code-from: Ricardo Neri Signed-off-by: Sai Praneeth Prakhya Signed-off-by: Ard Biesheuvel --- drivers/firmware/efi/runtime-wrappers.c | 53 +++++-------------------- include/linux/efi.h | 36 +++++++++++++++++ 2 files changed, 45 insertions(+), 44 deletions(-) diff --git a/drivers/firmware/efi/runtime-wrappers.c b/drivers/firmware/efi/runtime-wrappers.c index aa66cbf23512..b18b2d864c2c 100644 --- a/drivers/firmware/efi/runtime-wrappers.c +++ b/drivers/firmware/efi/runtime-wrappers.c @@ -45,39 +45,7 @@ #define __efi_call_virt(f, args...) \ __efi_call_virt_pointer(efi.systab->runtime, f, args) -/* efi_runtime_service() function identifiers */ -enum efi_rts_ids { - GET_TIME, - SET_TIME, - GET_WAKEUP_TIME, - SET_WAKEUP_TIME, - GET_VARIABLE, - GET_NEXT_VARIABLE, - SET_VARIABLE, - QUERY_VARIABLE_INFO, - GET_NEXT_HIGH_MONO_COUNT, - UPDATE_CAPSULE, - QUERY_CAPSULE_CAPS, -}; - -/* - * efi_runtime_work: Details of EFI Runtime Service work - * @arg<1-5>: EFI Runtime Service function arguments - * @status: Status of executing EFI Runtime Service - * @efi_rts_id: EFI Runtime Service function identifier - * @efi_rts_comp: Struct used for handling completions - */ -struct efi_runtime_work { - void *arg1; - void *arg2; - void *arg3; - void *arg4; - void *arg5; - efi_status_t status; - struct work_struct work; - enum efi_rts_ids efi_rts_id; - struct completion efi_rts_comp; -}; +struct efi_runtime_work efi_rts_work; /* * efi_queue_work: Queue efi_runtime_service() and wait until it's done @@ -91,7 +59,6 @@ struct efi_runtime_work { */ #define efi_queue_work(_rts, _arg1, _arg2, _arg3, _arg4, _arg5) \ ({ \ - struct efi_runtime_work efi_rts_work; \ efi_rts_work.status = EFI_ABORTED; \ \ init_completion(&efi_rts_work.efi_rts_comp); \ @@ -184,18 +151,16 @@ static DEFINE_SEMAPHORE(efi_runtime_lock); */ static void efi_call_rts(struct work_struct *work) { - struct efi_runtime_work *efi_rts_work; void *arg1, *arg2, *arg3, *arg4, *arg5; efi_status_t status = EFI_NOT_FOUND; - efi_rts_work = container_of(work, struct efi_runtime_work, work); - arg1 = efi_rts_work->arg1; - arg2 = efi_rts_work->arg2; - arg3 = efi_rts_work->arg3; - arg4 = efi_rts_work->arg4; - arg5 = efi_rts_work->arg5; + arg1 = efi_rts_work.arg1; + arg2 = efi_rts_work.arg2; + arg3 = efi_rts_work.arg3; + arg4 = efi_rts_work.arg4; + arg5 = efi_rts_work.arg5; - switch (efi_rts_work->efi_rts_id) { + switch (efi_rts_work.efi_rts_id) { case GET_TIME: status = efi_call_virt(get_time, (efi_time_t *)arg1, (efi_time_cap_t *)arg2); @@ -253,8 +218,8 @@ static void efi_call_rts(struct work_struct *work) */ pr_err("Requested executing invalid EFI Runtime Service.\n"); } - efi_rts_work->status = status; - complete(&efi_rts_work->efi_rts_comp); + efi_rts_work.status = status; + complete(&efi_rts_work.efi_rts_comp); } static efi_status_t virt_efi_get_time(efi_time_t *tm, efi_time_cap_t *tc) diff --git a/include/linux/efi.h b/include/linux/efi.h index 22e4de9d3700..a929d2bf41fa 100644 --- a/include/linux/efi.h +++ b/include/linux/efi.h @@ -1662,6 +1662,42 @@ struct linux_efi_tpm_eventlog { extern int efi_tpm_eventlog_init(void); +/* efi_runtime_service() function identifiers */ +enum efi_rts_ids { + GET_TIME, + SET_TIME, + GET_WAKEUP_TIME, + SET_WAKEUP_TIME, + GET_VARIABLE, + GET_NEXT_VARIABLE, + SET_VARIABLE, + QUERY_VARIABLE_INFO, + GET_NEXT_HIGH_MONO_COUNT, + UPDATE_CAPSULE, + QUERY_CAPSULE_CAPS, +}; + +/* + * efi_runtime_work: Details of EFI Runtime Service work + * @arg<1-5>: EFI Runtime Service function arguments + * @status: Status of executing EFI Runtime Service + * @efi_rts_id: EFI Runtime Service function identifier + * @efi_rts_comp: Struct used for handling completions + */ +struct efi_runtime_work { + void *arg1; + void *arg2; + void *arg3; + void *arg4; + void *arg5; + efi_status_t status; + struct work_struct work; + enum efi_rts_ids efi_rts_id; + struct completion efi_rts_comp; +}; + +extern struct efi_runtime_work efi_rts_work; + /* Workqueue to queue EFI Runtime Services */ extern struct workqueue_struct *efi_rts_wq; -- 2.18.0