From nobody Tue Feb 10 15:45:18 2026 Delivered-To: importer@patchew.org Received-SPF: pass (zoho.com: domain of gnu.org designates 208.118.235.17 as permitted sender) client-ip=208.118.235.17; envelope-from=qemu-devel-bounces+importer=patchew.org@nongnu.org; helo=lists.gnu.org; Authentication-Results: mx.zohomail.com; spf=pass (zoho.com: domain of gnu.org designates 208.118.235.17 as permitted sender) smtp.mailfrom=qemu-devel-bounces+importer=patchew.org@nongnu.org Return-Path: Received: from lists.gnu.org (lists.gnu.org [208.118.235.17]) by mx.zohomail.com with SMTPS id 1505149431436149.6403007187124; Mon, 11 Sep 2017 10:03:51 -0700 (PDT) Received: from localhost ([::1]:59171 helo=lists.gnu.org) by lists.gnu.org with esmtp (Exim 4.71) (envelope-from ) id 1drS7i-0000iz-L5 for importer@patchew.org; Mon, 11 Sep 2017 13:03:50 -0400 Received: from eggs.gnu.org ([2001:4830:134:3::10]:57640) by lists.gnu.org with esmtp (Exim 4.71) (envelope-from ) id 1drS3q-0005wf-6n for qemu-devel@nongnu.org; Mon, 11 Sep 2017 12:59:51 -0400 Received: from Debian-exim by eggs.gnu.org with spam-scanned (Exim 4.71) (envelope-from ) id 1drS3p-00077T-5Q for qemu-devel@nongnu.org; Mon, 11 Sep 2017 12:59:50 -0400 Received: from mx1.redhat.com ([209.132.183.28]:60366) by eggs.gnu.org with esmtps (TLS1.0:DHE_RSA_AES_256_CBC_SHA1:32) (Exim 4.71) (envelope-from ) id 1drS3o-000778-SI for qemu-devel@nongnu.org; Mon, 11 Sep 2017 12:59:49 -0400 Received: from smtp.corp.redhat.com (int-mx05.intmail.prod.int.phx2.redhat.com [10.5.11.15]) (using TLSv1.2 with cipher AECDH-AES256-SHA (256/256 bits)) (No client certificate requested) by mx1.redhat.com (Postfix) with ESMTPS id BABF4C00DBB0 for ; Mon, 11 Sep 2017 16:59:47 +0000 (UTC) Received: from localhost (ovpn-112-51.ams2.redhat.com [10.36.112.51]) by smtp.corp.redhat.com (Postfix) with ESMTP id 24BA46B25A; Mon, 11 Sep 2017 16:59:46 +0000 (UTC) DMARC-Filter: OpenDMARC Filter v1.3.2 mx1.redhat.com BABF4C00DBB0 Authentication-Results: ext-mx07.extmail.prod.ext.phx2.redhat.com; dmarc=none (p=none dis=none) header.from=redhat.com Authentication-Results: ext-mx07.extmail.prod.ext.phx2.redhat.com; spf=fail smtp.mailfrom=marcandre.lureau@redhat.com From: =?UTF-8?q?Marc-Andr=C3=A9=20Lureau?= To: qemu-devel@nongnu.org Date: Mon, 11 Sep 2017 18:59:25 +0200 Message-Id: <20170911165929.2791-4-marcandre.lureau@redhat.com> In-Reply-To: <20170911165929.2791-1-marcandre.lureau@redhat.com> References: <20170911165929.2791-1-marcandre.lureau@redhat.com> MIME-Version: 1.0 X-Scanned-By: MIMEDefang 2.79 on 10.5.11.15 X-Greylist: Sender IP whitelisted, not delayed by milter-greylist-4.5.16 (mx1.redhat.com [10.5.110.31]); Mon, 11 Sep 2017 16:59:47 +0000 (UTC) Content-Transfer-Encoding: quoted-printable X-detected-operating-system: by eggs.gnu.org: GNU/Linux 2.2.x-3.x [generic] [fuzzy] X-Received-From: 209.132.183.28 Subject: [Qemu-devel] [PATCH v6 3/7] dump: add guest ELF note X-BeenThere: qemu-devel@nongnu.org X-Mailman-Version: 2.1.21 Precedence: list List-Id: List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Cc: ehabkost@redhat.com, mst@redhat.com, anderson@redhat.com, =?UTF-8?q?Marc-Andr=C3=A9=20Lureau?= , imammedo@redhat.com, lersek@redhat.com Errors-To: qemu-devel-bounces+importer=patchew.org@nongnu.org Sender: "Qemu-devel" X-ZohoMail: RSF_0 Z_629925259 SPT_0 Content-Type: text/plain; charset="utf-8" Read the guest ELF PT_NOTE from guest memory when fw_cfg etc/vmcoreinfo entry provides the location, and write it as an additional note in the dump. Signed-off-by: Marc-Andr=C3=A9 Lureau --- include/sysemu/dump.h | 2 + dump.c | 107 ++++++++++++++++++++++++++++++++++++++++++++++= ++++ 2 files changed, 109 insertions(+) diff --git a/include/sysemu/dump.h b/include/sysemu/dump.h index 2672a15f8b..df43bd0e07 100644 --- a/include/sysemu/dump.h +++ b/include/sysemu/dump.h @@ -192,6 +192,8 @@ typedef struct DumpState { * this could be used to calculate * how much work we have * finished. */ + uint8_t *guest_note; /* ELF note content */ + size_t guest_note_size; } DumpState; =20 uint16_t cpu_to_dump16(DumpState *s, uint16_t val); diff --git a/dump.c b/dump.c index a79773d0f7..3cec6a8c93 100644 --- a/dump.c +++ b/dump.c @@ -26,6 +26,8 @@ #include "qapi/qmp/qerror.h" #include "qmp-commands.h" #include "qapi-event.h" +#include "qemu/error-report.h" +#include "hw/misc/vmcoreinfo.h" =20 #include #ifdef CONFIG_LZO @@ -38,6 +40,13 @@ #define ELF_MACHINE_UNAME "Unknown" #endif =20 +#define MAX_GUEST_NOTE_SIZE (1 << 20) /* 1MB should be enough */ + +#define ELF_NOTE_SIZE(hdr_size, name_size, desc_size) \ + ((DIV_ROUND_UP((hdr_size), 4) + \ + DIV_ROUND_UP((name_size), 4) + \ + DIV_ROUND_UP((desc_size), 4)) * 4) + uint16_t cpu_to_dump16(DumpState *s, uint16_t val) { if (s->dump_info.d_endian =3D=3D ELFDATA2LSB) { @@ -76,6 +85,8 @@ static int dump_cleanup(DumpState *s) guest_phys_blocks_free(&s->guest_phys_blocks); memory_mapping_list_free(&s->list); close(s->fd); + g_free(s->guest_note); + s->guest_note =3D NULL; if (s->resume) { if (s->detached) { qemu_mutex_lock_iothread(); @@ -235,6 +246,19 @@ static inline int cpu_index(CPUState *cpu) return cpu->cpu_index + 1; } =20 +static void write_guest_note(WriteCoreDumpFunction f, DumpState *s, + Error **errp) +{ + int ret; + + if (s->guest_note) { + ret =3D f(s->guest_note, s->guest_note_size, s); + if (ret < 0) { + error_setg(errp, "dump: failed to write guest note"); + } + } +} + static void write_elf64_notes(WriteCoreDumpFunction f, DumpState *s, Error **errp) { @@ -258,6 +282,8 @@ static void write_elf64_notes(WriteCoreDumpFunction f, = DumpState *s, return; } } + + write_guest_note(f, s, errp); } =20 static void write_elf32_note(DumpState *s, Error **errp) @@ -303,6 +329,8 @@ static void write_elf32_notes(WriteCoreDumpFunction f, = DumpState *s, return; } } + + write_guest_note(f, s, errp); } =20 static void write_elf_section(DumpState *s, int type, Error **errp) @@ -714,6 +742,44 @@ static int buf_write_note(const void *buf, size_t size= , void *opaque) return 0; } =20 +/* + * This function retrieves various sizes from an elf header. + * + * @note has to be a valid ELF note. The return sizes are unmodified + * (not padded or rounded up to be multiple of 4). + */ +static void get_note_sizes(DumpState *s, const void *note, + uint64_t *note_head_size, + uint64_t *name_size, + uint64_t *desc_size) +{ + uint64_t note_head_sz; + uint64_t name_sz; + uint64_t desc_sz; + + if (s->dump_info.d_class =3D=3D ELFCLASS64) { + const Elf64_Nhdr *hdr =3D note; + note_head_sz =3D sizeof(Elf64_Nhdr); + name_sz =3D tswap64(hdr->n_namesz); + desc_sz =3D tswap64(hdr->n_descsz); + } else { + const Elf32_Nhdr *hdr =3D note; + note_head_sz =3D sizeof(Elf32_Nhdr); + name_sz =3D tswap32(hdr->n_namesz); + desc_sz =3D tswap32(hdr->n_descsz); + } + + if (note_head_size) { + *note_head_size =3D note_head_sz; + } + if (name_size) { + *name_size =3D name_sz; + } + if (desc_size) { + *desc_size =3D desc_sz; + } +} + /* write common header, sub header and elf note to vmcore */ static void create_header32(DumpState *s, Error **errp) { @@ -1492,6 +1558,7 @@ static void dump_init(DumpState *s, int fd, bool has_= format, DumpGuestMemoryFormat format, bool paging, bool has_= filter, int64_t begin, int64_t length, Error **errp) { + VMCoreInfoState *vmci =3D vmcoreinfo_find(); CPUState *cpu; int nr_cpus; Error *err =3D NULL; @@ -1563,6 +1630,46 @@ static void dump_init(DumpState *s, int fd, bool has= _format, goto cleanup; } =20 + /* + * The goal of this block is to copy the guest note out of + * the guest. Failure to do so is not fatal for dumping. + */ + if (vmci) { + uint64_t addr, note_head_size, name_size, desc_size; + uint32_t size; + uint16_t format; + + note_head_size =3D s->dump_info.d_class =3D=3D ELFCLASS32 ? + sizeof(Elf32_Nhdr) : sizeof(Elf64_Nhdr); + + format =3D le16_to_cpu(vmci->vmcoreinfo.guest_format); + size =3D le32_to_cpu(vmci->vmcoreinfo.size); + addr =3D le64_to_cpu(vmci->vmcoreinfo.paddr); + if (!vmci->has_vmcoreinfo) { + warn_report("guest note is not present"); + } else if (size < note_head_size || size > MAX_GUEST_NOTE_SIZE) { + warn_report("guest note size is invalid: %" PRIu32, size); + } else if (format !=3D VMCOREINFO_FORMAT_ELF) { + warn_report("guest note format is unsupported: %" PRIu16, form= at); + } else { + s->guest_note =3D g_malloc(size + 1); /* +1 for adding \0 */ + cpu_physical_memory_read(addr, s->guest_note, size); + + get_note_sizes(s, s->guest_note, NULL, &name_size, &desc_size); + s->guest_note_size =3D ELF_NOTE_SIZE(note_head_size, name_size, + desc_size); + if (name_size > MAX_GUEST_NOTE_SIZE || + desc_size > MAX_GUEST_NOTE_SIZE || + s->guest_note_size > size) { + warn_report("Invalid guest note header"); + g_free(s->guest_note); + s->guest_note =3D NULL; + } else { + s->note_size +=3D s->guest_note_size; + } + } + } + /* get memory mapping */ if (paging) { qemu_get_guest_memory_mapping(&s->list, &s->guest_phys_blocks, &er= r); --=20 2.14.1.146.gd35faa819