From patchwork Tue Oct 23 23:57:44 2018 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Brendan Higgins X-Patchwork-Id: 10654155 Return-Path: Received: from mail.wl.linuxfoundation.org (pdx-wl-mail.web.codeaurora.org [172.30.200.125]) by pdx-korg-patchwork-2.web.codeaurora.org (Postfix) with ESMTP id 5D94F14BD for ; Wed, 24 Oct 2018 04:06:28 +0000 (UTC) Received: from mail.wl.linuxfoundation.org (localhost [127.0.0.1]) by mail.wl.linuxfoundation.org (Postfix) with ESMTP id 4634B29DC9 for ; Wed, 24 Oct 2018 04:06:28 +0000 (UTC) Received: by mail.wl.linuxfoundation.org (Postfix, from userid 486) id 3687229DF8; Wed, 24 Oct 2018 04:06:28 +0000 (UTC) X-Spam-Checker-Version: SpamAssassin 3.3.1 (2010-03-16) on pdx-wl-mail.web.codeaurora.org X-Spam-Level: X-Spam-Status: No, score=-13.9 required=2.0 tests=BAYES_00,DATE_IN_PAST_03_06, DKIM_SIGNED,DKIM_VALID,DKIM_VALID_AU,MAILING_LIST_MULTI,RCVD_IN_DNSWL_HI, USER_IN_DEF_DKIM_WL autolearn=ham version=3.3.1 Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.wl.linuxfoundation.org (Postfix) with ESMTP id C38AF29DC9 for ; Wed, 24 Oct 2018 04:06:27 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1726240AbeJXMcp (ORCPT ); Wed, 24 Oct 2018 08:32:45 -0400 Received: from mail-pf1-f202.google.com ([209.85.210.202]:36737 "EHLO mail-pf1-f202.google.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1726082AbeJXMcp (ORCPT ); Wed, 24 Oct 2018 08:32:45 -0400 Received: by mail-pf1-f202.google.com with SMTP id q18-v6so2461717pfk.3 for ; Tue, 23 Oct 2018 21:06:26 -0700 (PDT) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=google.com; s=20161025; h=date:in-reply-to:message-id:mime-version:references:subject:from:to :cc; bh=AZXGizRDYB34OjNAQjmrfiUD+eNMXlsWMwWZ+590v6s=; b=WPSOrUggU3rnluD6CS22h/UnyXqz+yZgPhghBy1ulhS1ExIvkAlgrPhT2pxavu/1Yy /M40uBDuFS/4BLISVGD2wj64ZxwEpD2qeFrLkiswC9i0L9hxosRGOVWsaVfMHjE5FvGr g79xGMLyciKHemaRWT56krnP6UJujxt5kaMn8WSJaoJwxTiNjRukz0B1zjtDGsnlPF+j oGrxUJa7w0u2dw4cUSntMXlUdM2cO4WeX/hemjsNn3JuNvqsObmNw14i9i6V6bk2XlJ0 eAUrn1wx5scw40yF22chLWPdwFc02fYz0s/RtLtbYteaFDBgQeDwtBEuaCIWIFNYKcah FQeg== X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20161025; h=x-gm-message-state:date:in-reply-to:message-id:mime-version :references:subject:from:to:cc; bh=AZXGizRDYB34OjNAQjmrfiUD+eNMXlsWMwWZ+590v6s=; b=tJXvQKGj4IUxBFeLrFTuD6ZCU3DiEunW+hX83wWWo5ZmOOaDluSK32ZiGd3P99plAM u377z07uM5WtY0zjLwk/nTzZA5cj51tiREHt/51P3M/Ho0aR74OZV9aL9gc76M5JAeiy vHKdV7FhJWvM0064frWJaE115EwWouHNFP01pV6YayYlrIWzLwK8i+xgnDuZGqThuhAp /VkpFVMT1wOMfaf/iIjp2vNtftRqnoosUipgZoR15IR6deZc+dDRtKDZxhcQXHI0Y3d0 K5WwWDvwj0MeEARW4k+RXm66RTmGM4SuecX32dVWAQ6KDxKMGqBgaFqX1AIbYTiQYYqW eBFA== X-Gm-Message-State: AGRZ1gJ/NCWKbGupvHb1sMmeqlQ/nSxcDmaPhtr0NsDzXHT0SICtgwZc EcFzB+iMOGHq3LvYxvupWoDcrw0VZia0K3gKf2MfYQ== X-Google-Smtp-Source: AJdET5eqXAp+/iws1KPP7vDDWFDc90iv2ui+fE+0/W/M6tvyz4dYd5p4tqPvTkGZUaE8z6wekIB4P0Fo77lczqOisUKd/Q== X-Received: by 2002:a63:f1d:: with SMTP id e29-v6mr249762pgl.13.1540339197533; Tue, 23 Oct 2018 16:59:57 -0700 (PDT) Date: Tue, 23 Oct 2018 16:57:44 -0700 In-Reply-To: <20181023235750.103146-1-brendanhiggins@google.com> Message-Id: <20181023235750.103146-9-brendanhiggins@google.com> Mime-Version: 1.0 References: <20181023235750.103146-1-brendanhiggins@google.com> X-Mailer: git-send-email 2.19.1.568.g152ad8e336-goog Subject: [RFC v2 08/14] arch: um: add shim to trap to allow installing a fault catcher for tests From: Brendan Higgins To: gregkh@linuxfoundation.org, keescook@google.com, mcgrof@kernel.org, shuah@kernel.org Cc: joel@jms.id.au, mpe@ellerman.id.au, joe@perches.com, brakmo@fb.com, rostedt@goodmis.org, Tim.Bird@sony.com, khilman@baylibre.com, julia.lawall@lip6.fr, linux-kselftest@vger.kernel.org, kunit-dev@googlegroups.com, linux-kernel@vger.kernel.org, jdike@addtoit.com, richard@nod.at, linux-um@lists.infradead.org, daniel@ffwll.ch, dri-devel@lists.freedesktop.org, robh@kernel.org, dan.j.williams@intel.com, linux-nvdimm@lists.01.org, kieran.bingham@ideasonboard.com, Brendan Higgins Sender: linux-kselftest-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-kselftest@vger.kernel.org X-Virus-Scanned: ClamAV using ClamSMTP Add context to current thread that allows a test to specify that it wants to skip the normal checks to run an installed fault catcher. Signed-off-by: Brendan Higgins --- arch/um/include/asm/processor-generic.h | 4 +++- arch/um/kernel/trap.c | 15 +++++++++++---- 2 files changed, 14 insertions(+), 5 deletions(-) diff --git a/arch/um/include/asm/processor-generic.h b/arch/um/include/asm/processor-generic.h index b58b746d3f2ca..d566cd416ff02 100644 --- a/arch/um/include/asm/processor-generic.h +++ b/arch/um/include/asm/processor-generic.h @@ -27,6 +27,7 @@ struct thread_struct { struct task_struct *prev_sched; struct arch_thread arch; jmp_buf switch_buf; + bool is_running_test; struct { int op; union { @@ -51,7 +52,8 @@ struct thread_struct { .fault_addr = NULL, \ .prev_sched = NULL, \ .arch = INIT_ARCH_THREAD, \ - .request = { 0 } \ + .request = { 0 }, \ + .is_running_test = false, \ } static inline void release_thread(struct task_struct *task) diff --git a/arch/um/kernel/trap.c b/arch/um/kernel/trap.c index cced829460427..bf90e678b3d71 100644 --- a/arch/um/kernel/trap.c +++ b/arch/um/kernel/trap.c @@ -201,6 +201,12 @@ void segv_handler(int sig, struct siginfo *unused_si, struct uml_pt_regs *regs) segv(*fi, UPT_IP(regs), UPT_IS_USER(regs), regs); } +static void segv_run_catcher(jmp_buf *catcher, void *fault_addr) +{ + current->thread.fault_addr = fault_addr; + UML_LONGJMP(catcher, 1); +} + /* * We give a *copy* of the faultinfo in the regs to segv. * This must be done, since nesting SEGVs could overwrite @@ -219,7 +225,10 @@ unsigned long segv(struct faultinfo fi, unsigned long ip, int is_user, if (!is_user && regs) current->thread.segv_regs = container_of(regs, struct pt_regs, regs); - if (!is_user && (address >= start_vm) && (address < end_vm)) { + catcher = current->thread.fault_catcher; + if (catcher && current->thread.is_running_test) + segv_run_catcher(catcher, (void *) address); + else if (!is_user && (address >= start_vm) && (address < end_vm)) { flush_tlb_kernel_vm(); goto out; } @@ -246,12 +255,10 @@ unsigned long segv(struct faultinfo fi, unsigned long ip, int is_user, address = 0; } - catcher = current->thread.fault_catcher; if (!err) goto out; else if (catcher != NULL) { - current->thread.fault_addr = (void *) address; - UML_LONGJMP(catcher, 1); + segv_run_catcher(catcher, (void *) address); } else if (current->thread.fault_addr != NULL) panic("fault_addr set but no fault catcher");