From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: from mail-qk1-x742.google.com (mail-qk1-x742.google.com [IPv6:2607:f8b0:4864:20::742]) by sourceware.org (Postfix) with ESMTPS id 34E26382E04F for ; Wed, 15 Jul 2020 19:49:08 +0000 (GMT) DMARC-Filter: OpenDMARC Filter v1.3.2 sourceware.org 34E26382E04F Received: by mail-qk1-x742.google.com with SMTP id b185so3061486qkg.1 for ; Wed, 15 Jul 2020 12:49:08 -0700 (PDT) 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=eHaSmyNzpUYR7n8hy8ayqLYkp7VIG7vRP0ic9UTwn7E=; b=h6lKzHfokIPCb9U4C4BrTR6PISbbQxW/JYKjaQ5IFgb2yyBIE4SjiB6aOFmfUhELj3 Ue40X8rIP67s+WsVcVPvMwHw8gxzXnXY0VbTxL8zK6VPPm43DFMCZgj7pZoXtppCqCC1 7ROecWpxZoSNOEtflts3XayGvqUTzC1pZMNZlg1ndexfYiorGwKAR9y0B+IYDkf7UUal ZAvhIx3GsYnJQ+ec0cqYN4tHgoVhd7O3OuolTOT251aZSjkNKkEqE0+rLiLAYPkZo8+q +ti14ow8pJPAK23l/xS1NAImip/oR2irPoygwiHFwZUOLLEi2jU26FNd/y5Wzgauzc7g aooQ== X-Gm-Message-State: AOAM532jKr0mbmNku3KpTulw3kdPVZarVNYXIVPwrgIRAtVyj3flVr+I k0Me5oT73boy5LMv7LfBIIASuSuKIbPRng== X-Google-Smtp-Source: ABdhPJy/0yJUcchUDttZmb0ltLCBAB9G28/uNM0LW2KL/wbruv1UAeJcIIMZPhSfw964J/RmdW6X3Q== X-Received: by 2002:a37:6150:: with SMTP id v77mr707131qkb.173.1594842547491; Wed, 15 Jul 2020 12:49:07 -0700 (PDT) Received: from localhost.localdomain ([2804:7f0:8283:82c3:9daa:7611:ebe6:931]) by smtp.gmail.com with ESMTPSA id z18sm4340537qta.51.2020.07.15.12.48.56 (version=TLS1_3 cipher=TLS_AES_256_GCM_SHA384 bits=256/256); Wed, 15 Jul 2020 12:49:07 -0700 (PDT) From: Luis Machado To: gdb-patches@sourceware.org, Alan.Hayward@arm.com Cc: omair.javaid@linaro.org, catalin.marinas@arm.com, david.spickett@linaro.org, jose.marchesi@oracle.com Subject: [PATCH 16/23] AArch64: Report tag violation error information Date: Wed, 15 Jul 2020 16:45:06 -0300 Message-Id: <20200715194513.16641-17-luis.machado@linaro.org> X-Mailer: git-send-email 2.17.1 In-Reply-To: <20200715194513.16641-1-luis.machado@linaro.org> References: <20200715194513.16641-1-luis.machado@linaro.org> X-Spam-Status: No, score=-10.7 required=5.0 tests=BAYES_00, DKIM_SIGNED, DKIM_VALID, DKIM_VALID_AU, DKIM_VALID_EF, GIT_PATCH_0, RCVD_IN_DNSWL_NONE, SPF_HELO_NONE, SPF_PASS, TXREP autolearn=ham autolearn_force=no version=3.4.2 X-Spam-Checker-Version: SpamAssassin 3.4.2 (2018-09-13) on server2.sourceware.org X-BeenThere: gdb-patches@sourceware.org X-Mailman-Version: 2.1.29 Precedence: list List-Id: Gdb-patches mailing list List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , X-List-Received-Date: Wed, 15 Jul 2020 19:49:09 -0000 Whenever a memory tag violation occurs, we get a SIGSEGV. Additional information can be obtained through the siginfo data structure. For AArch64 the Linux kernel may expose the fault address and tag information, if we have a synchronous event. Otherwise there is no fault address available. gdb/ChangeLog: YYYY-MM-DD Luis Machado * aarch64-linux-tdep.c (aarch64_linux_handle_segmentation_fault): New function. (aarch64_linux_init_abi): Register aarch64_linux_handle_segmentation_fault as segmentation fault hook. * arch/aarch64-linux.h (SEGV_MTEAERR): Define. (SEGV_MTESERR): Define. --- gdb/aarch64-linux-tdep.c | 58 ++++++++++++++++++++++++++++++++++++ gdb/arch/aarch64-mte-linux.h | 6 ++++ 2 files changed, 64 insertions(+) diff --git a/gdb/aarch64-linux-tdep.c b/gdb/aarch64-linux-tdep.c index 5cb66fbb14..e89e3a5467 100644 --- a/gdb/aarch64-linux-tdep.c +++ b/gdb/aarch64-linux-tdep.c @@ -1626,6 +1626,61 @@ aarch64_linux_memtag_to_string (struct gdbarch *gdbarch, return string_printf ("0x%s", phex_nz (tag, sizeof (tag))); } +/* AArch64 Linux implementation of the handle_segmentation_fault gdbarch + hook. Displays information about possible memory tag violations. */ + +static void +aarch64_linux_handle_segmentation_fault (struct gdbarch *gdbarch, + struct ui_out *uiout) +{ + CORE_ADDR fault_addr = 0; + long si_code = 0; + + try + { + /* Sigcode tells us if the segfault is actually a memory tag + violation. */ + si_code = parse_and_eval_long ("$_siginfo.si_code\n"); + + fault_addr + = parse_and_eval_long ("$_siginfo._sifields._sigfault.si_addr"); + } + catch (const gdb_exception &exception) + { + return; + } + + /* If this is not a memory tag violation, just return. */ + if (si_code != SEGV_MTEAERR && si_code != SEGV_MTESERR) + return; + + uiout->text ("\n"); + + uiout->field_string ("sigcode-meaning", _("Memory tag violation")); + + /* For synchronous faults, show additional information. */ + if (si_code == SEGV_MTESERR) + { + uiout->text (_(" while accessing address ")); + uiout->field_core_addr ("fault-addr", gdbarch, fault_addr); + uiout->text ("\n"); + + CORE_ADDR atag; + if (aarch64_linux_get_atag (fault_addr, &atag) != 0) + uiout->text (_("Allocation tag unavailable")); + else + { + uiout->text (_("Allocation tag ")); + uiout->field_core_addr ("allocation-tag", gdbarch, atag); + } + } + else + { + uiout->text ("\n"); + uiout->text (_("Fault address unavailable")); + } +} + static void aarch64_linux_init_abi (struct gdbarch_info info, struct gdbarch *gdbarch) { @@ -1706,6 +1761,9 @@ aarch64_linux_init_abi (struct gdbarch_info info, struct gdbarch *gdbarch) /* Register a hook for converting a memory tag to a string. */ set_gdbarch_memtag_to_string (gdbarch, aarch64_linux_memtag_to_string); + + set_gdbarch_handle_segmentation_fault (gdbarch, + aarch64_linux_handle_segmentation_fault); } /* Initialize the aarch64_linux_record_tdep. */ diff --git a/gdb/arch/aarch64-mte-linux.h b/gdb/arch/aarch64-mte-linux.h index 5c5783f28b..a5a980ed49 100644 --- a/gdb/arch/aarch64-mte-linux.h +++ b/gdb/arch/aarch64-mte-linux.h @@ -35,6 +35,12 @@ #define MTE_LOGICAL_TAG_START_BIT 56 #define MTE_LOGICAL_MAX_VALUE 0xf +/* Memory tagging definitions. */ +#ifndef SEGV_MTEAERR +# define SEGV_MTEAERR 8 +# define SEGV_MTESERR 9 +#endif + /* Return the number of tag granules in the memory range [ADDR, ADDR + LEN) given GRANULE_SIZE. */ extern size_t get_tag_granules (CORE_ADDR addr, size_t len, -- 2.17.1