From patchwork Tue May 28 16:15:07 2024 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Michal Privoznik X-Patchwork-Id: 1940642 Return-Path: X-Original-To: incoming@patchwork.ozlabs.org Delivered-To: patchwork-incoming@legolas.ozlabs.org Authentication-Results: legolas.ozlabs.org; dkim=pass (1024-bit key; unprotected) header.d=redhat.com header.i=@redhat.com header.a=rsa-sha256 header.s=mimecast20190719 header.b=eqWupJN8; dkim-atps=neutral Authentication-Results: legolas.ozlabs.org; spf=pass (sender SPF authorized) smtp.mailfrom=nongnu.org (client-ip=209.51.188.17; helo=lists.gnu.org; envelope-from=qemu-devel-bounces+incoming=patchwork.ozlabs.org@nongnu.org; receiver=patchwork.ozlabs.org) Received: from lists.gnu.org (lists.gnu.org [209.51.188.17]) (using TLSv1.2 with cipher ECDHE-ECDSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by legolas.ozlabs.org (Postfix) with ESMTPS id 4Vpd1Z5d6Gz20Q3 for ; Wed, 29 May 2024 02:16:34 +1000 (AEST) Received: from localhost ([::1] helo=lists1p.gnu.org) by lists.gnu.org with esmtp (Exim 4.90_1) (envelope-from ) id 1sBzTu-0003T5-U9; Tue, 28 May 2024 12:15:22 -0400 Received: from eggs.gnu.org ([2001:470:142:3::10]) by lists.gnu.org with esmtps (TLS1.2:ECDHE_RSA_AES_256_GCM_SHA384:256) (Exim 4.90_1) (envelope-from ) id 1sBzTt-0003SD-59 for qemu-devel@nongnu.org; Tue, 28 May 2024 12:15:21 -0400 Received: from us-smtp-delivery-124.mimecast.com ([170.10.129.124]) by eggs.gnu.org with esmtps (TLS1.2:ECDHE_RSA_AES_256_GCM_SHA384:256) (Exim 4.90_1) (envelope-from ) id 1sBzTr-0001ib-IC for qemu-devel@nongnu.org; Tue, 28 May 2024 12:15:20 -0400 DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=redhat.com; s=mimecast20190719; t=1716912918; h=from:from:reply-to:subject:subject:date:date:message-id:message-id: to:to:cc:cc:mime-version:mime-version: content-transfer-encoding:content-transfer-encoding: in-reply-to:in-reply-to:references:references; bh=a8S6mW08ZFnf4Hy8qt0xgV8FecjvZuL0DLHEmVYF3fI=; b=eqWupJN81U1gzmuy8KtagtgvjwoxYa+LPojZQFxV+RnWLNoGPcjg5m8A2PSHgsq7dK85Ze kdtRh84lIRdG/aAid72rXt2kTPu4Cg5xo+Xmpn4RGxuPKyngo71UydG3TlbQIeZrirHAr4 qvKOV5Rks+MMM1lL8EVkJxbtwUYNErg= Received: from mimecast-mx02.redhat.com (mimecast-mx02.redhat.com [66.187.233.88]) by relay.mimecast.com with ESMTP with STARTTLS (version=TLSv1.3, cipher=TLS_AES_256_GCM_SHA384) id us-mta-139-YcXACB2fO6226lg_b1INYg-1; Tue, 28 May 2024 12:15:16 -0400 X-MC-Unique: YcXACB2fO6226lg_b1INYg-1 Received: from smtp.corp.redhat.com (int-mx08.intmail.prod.int.rdu2.redhat.com [10.11.54.8]) (using TLSv1.3 with cipher TLS_AES_256_GCM_SHA384 (256/256 bits) key-exchange X25519 server-signature RSA-PSS (2048 bits) server-digest SHA256) (No client certificate requested) by mimecast-mx02.redhat.com (Postfix) with ESMTPS id 4A6CB80118E for ; Tue, 28 May 2024 16:15:16 +0000 (UTC) Received: from maggie.brq.redhat.com (unknown [10.43.3.102]) by smtp.corp.redhat.com (Postfix) with ESMTP id 75D02C15BC3; Tue, 28 May 2024 16:15:15 +0000 (UTC) From: Michal Privoznik To: qemu-devel@nongnu.org Cc: david@redhat.com, imammedo@redhat.com Subject: [PATCH 1/3] osdep: Make qemu_madvise() to set errno in all cases Date: Tue, 28 May 2024 18:15:07 +0200 Message-ID: <4d8a74a512bf55f39c5d1be115b1c52b6a632e09.1716912651.git.mprivozn@redhat.com> In-Reply-To: References: MIME-Version: 1.0 X-Scanned-By: MIMEDefang 3.4.1 on 10.11.54.8 Received-SPF: pass client-ip=170.10.129.124; envelope-from=mprivozn@redhat.com; helo=us-smtp-delivery-124.mimecast.com X-Spam_score_int: -20 X-Spam_score: -2.1 X-Spam_bar: -- X-Spam_report: (-2.1 / 5.0 requ) BAYES_00=-1.9, DKIMWL_WL_HIGH=-0.034, DKIM_SIGNED=0.1, DKIM_VALID=-0.1, DKIM_VALID_AU=-0.1, DKIM_VALID_EF=-0.1, RCVD_IN_DNSWL_NONE=-0.0001, RCVD_IN_MSPIKE_H4=0.001, RCVD_IN_MSPIKE_WL=0.001, SPF_HELO_NONE=0.001, SPF_PASS=-0.001, T_SCC_BODY_TEXT_LINE=-0.01 autolearn=ham autolearn_force=no X-Spam_action: no action X-BeenThere: qemu-devel@nongnu.org X-Mailman-Version: 2.1.29 Precedence: list List-Id: List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Errors-To: qemu-devel-bounces+incoming=patchwork.ozlabs.org@nongnu.org Sender: qemu-devel-bounces+incoming=patchwork.ozlabs.org@nongnu.org The unspoken premise of qemu_madvise() is that errno is set on error. And it is mostly the case except for posix_madvise() which is documented to return either zero (on success) or a positive error number. This means, we must set errno ourselves. And while at it, make the function return a negative value on error, just like other error paths do. Signed-off-by: Michal Privoznik Reviewed-by: David Hildenbrand --- util/osdep.c | 7 ++++++- 1 file changed, 6 insertions(+), 1 deletion(-) diff --git a/util/osdep.c b/util/osdep.c index e996c4744a..e42f4e8121 100644 --- a/util/osdep.c +++ b/util/osdep.c @@ -57,7 +57,12 @@ int qemu_madvise(void *addr, size_t len, int advice) #if defined(CONFIG_MADVISE) return madvise(addr, len, advice); #elif defined(CONFIG_POSIX_MADVISE) - return posix_madvise(addr, len, advice); + int rc = posix_madvise(addr, len, advice); + if (rc) { + errno = rc; + return -1; + } + return 0; #else errno = EINVAL; return -1; From patchwork Tue May 28 16:15:08 2024 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Michal Privoznik X-Patchwork-Id: 1940643 Return-Path: X-Original-To: incoming@patchwork.ozlabs.org Delivered-To: patchwork-incoming@legolas.ozlabs.org Authentication-Results: legolas.ozlabs.org; dkim=pass (1024-bit key; unprotected) header.d=redhat.com header.i=@redhat.com header.a=rsa-sha256 header.s=mimecast20190719 header.b=PHq/RjAj; dkim-atps=neutral Authentication-Results: legolas.ozlabs.org; spf=pass (sender SPF authorized) smtp.mailfrom=nongnu.org (client-ip=209.51.188.17; helo=lists.gnu.org; envelope-from=qemu-devel-bounces+incoming=patchwork.ozlabs.org@nongnu.org; receiver=patchwork.ozlabs.org) Received: from lists.gnu.org (lists.gnu.org [209.51.188.17]) (using TLSv1.2 with cipher ECDHE-ECDSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by legolas.ozlabs.org (Postfix) with ESMTPS id 4Vpd1b5P6Nz20f1 for ; Wed, 29 May 2024 02:16:35 +1000 (AEST) Received: from localhost ([::1] helo=lists1p.gnu.org) by lists.gnu.org with esmtp (Exim 4.90_1) (envelope-from ) id 1sBzTv-0003Ta-Ps; Tue, 28 May 2024 12:15:23 -0400 Received: from eggs.gnu.org ([2001:470:142:3::10]) by lists.gnu.org with esmtps (TLS1.2:ECDHE_RSA_AES_256_GCM_SHA384:256) (Exim 4.90_1) (envelope-from ) id 1sBzTu-0003St-Mh for qemu-devel@nongnu.org; Tue, 28 May 2024 12:15:22 -0400 Received: from us-smtp-delivery-124.mimecast.com ([170.10.129.124]) by eggs.gnu.org with esmtps (TLS1.2:ECDHE_RSA_AES_256_GCM_SHA384:256) (Exim 4.90_1) (envelope-from ) id 1sBzTt-0001ir-5U for qemu-devel@nongnu.org; Tue, 28 May 2024 12:15:22 -0400 DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=redhat.com; s=mimecast20190719; t=1716912920; h=from:from:reply-to:subject:subject:date:date:message-id:message-id: to:to:cc:cc:mime-version:mime-version: content-transfer-encoding:content-transfer-encoding: in-reply-to:in-reply-to:references:references; bh=0bOdMPqUA+lkNbcV85HXskFJU4DMfBPjohOMFYIhyoQ=; b=PHq/RjAjrXLDuM9zvZ27BhNGegdj9mTA00c5UJ6Bau6of+iWvdC/8vspS7lTs3dd3fkHEf 0vo1WIPhV6r2i6e9o7UUlvaOpp5Q8ndAdbm2w+veK4o+juERyFZN4BLUmZ30rJNuwY6lvM r8XsO9ymlwRbEONPu1n84+mn/otYhU0= Received: from mimecast-mx02.redhat.com (mx-ext.redhat.com [66.187.233.73]) by relay.mimecast.com with ESMTP with STARTTLS (version=TLSv1.3, cipher=TLS_AES_256_GCM_SHA384) id us-mta-657-6eNjhpCPOwCxwV3KYzG0Tw-1; Tue, 28 May 2024 12:15:17 -0400 X-MC-Unique: 6eNjhpCPOwCxwV3KYzG0Tw-1 Received: from smtp.corp.redhat.com (int-mx08.intmail.prod.int.rdu2.redhat.com [10.11.54.8]) (using TLSv1.3 with cipher TLS_AES_256_GCM_SHA384 (256/256 bits) key-exchange X25519 server-signature RSA-PSS (2048 bits) server-digest SHA256) (No client certificate requested) by mimecast-mx02.redhat.com (Postfix) with ESMTPS id 4CEA51C0512D for ; Tue, 28 May 2024 16:15:17 +0000 (UTC) Received: from maggie.brq.redhat.com (unknown [10.43.3.102]) by smtp.corp.redhat.com (Postfix) with ESMTP id 7B1A7C15BB9; Tue, 28 May 2024 16:15:16 +0000 (UTC) From: Michal Privoznik To: qemu-devel@nongnu.org Cc: david@redhat.com, imammedo@redhat.com Subject: [PATCH 2/3] backends/hostmem: Warn on qemu_madvise() failures Date: Tue, 28 May 2024 18:15:08 +0200 Message-ID: In-Reply-To: References: MIME-Version: 1.0 X-Scanned-By: MIMEDefang 3.4.1 on 10.11.54.8 Received-SPF: pass client-ip=170.10.129.124; envelope-from=mprivozn@redhat.com; helo=us-smtp-delivery-124.mimecast.com X-Spam_score_int: -20 X-Spam_score: -2.1 X-Spam_bar: -- X-Spam_report: (-2.1 / 5.0 requ) BAYES_00=-1.9, DKIMWL_WL_HIGH=-0.034, DKIM_SIGNED=0.1, DKIM_VALID=-0.1, DKIM_VALID_AU=-0.1, DKIM_VALID_EF=-0.1, RCVD_IN_DNSWL_NONE=-0.0001, RCVD_IN_MSPIKE_H4=0.001, RCVD_IN_MSPIKE_WL=0.001, SPF_HELO_NONE=0.001, SPF_PASS=-0.001, T_SCC_BODY_TEXT_LINE=-0.01 autolearn=ham autolearn_force=no X-Spam_action: no action X-BeenThere: qemu-devel@nongnu.org X-Mailman-Version: 2.1.29 Precedence: list List-Id: List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Errors-To: qemu-devel-bounces+incoming=patchwork.ozlabs.org@nongnu.org Sender: qemu-devel-bounces+incoming=patchwork.ozlabs.org@nongnu.org If user sets .merge or .dump attributes qemu_madvise() is called with corresponding advice. But it is never checked for failure which may mislead users into thinking the attribute is set correctly.I believe at this point it's too late to report errors in that case but let's report a warning at least. Signed-off-by: Michal Privoznik --- backends/hostmem.c | 27 +++++++++++++++++++-------- 1 file changed, 19 insertions(+), 8 deletions(-) diff --git a/backends/hostmem.c b/backends/hostmem.c index eb9682b4a8..1a6fd1c714 100644 --- a/backends/hostmem.c +++ b/backends/hostmem.c @@ -14,6 +14,7 @@ #include "sysemu/hostmem.h" #include "hw/boards.h" #include "qapi/error.h" +#include "qemu/error-report.h" #include "qapi/qapi-builtin-visit.h" #include "qapi/visitor.h" #include "qemu/config-file.h" @@ -178,8 +179,11 @@ static void host_memory_backend_set_merge(Object *obj, bool value, Error **errp) void *ptr = memory_region_get_ram_ptr(&backend->mr); uint64_t sz = memory_region_size(&backend->mr); - qemu_madvise(ptr, sz, - value ? QEMU_MADV_MERGEABLE : QEMU_MADV_UNMERGEABLE); + if (qemu_madvise(ptr, sz, + value ? QEMU_MADV_MERGEABLE : QEMU_MADV_UNMERGEABLE)) { + warn_report("Couldn't change property 'merge' on '%s': %s", + object_get_typename(obj), strerror(errno)); + } backend->merge = value; } } @@ -204,8 +208,11 @@ static void host_memory_backend_set_dump(Object *obj, bool value, Error **errp) void *ptr = memory_region_get_ram_ptr(&backend->mr); uint64_t sz = memory_region_size(&backend->mr); - qemu_madvise(ptr, sz, - value ? QEMU_MADV_DODUMP : QEMU_MADV_DONTDUMP); + if (qemu_madvise(ptr, sz, + value ? QEMU_MADV_DODUMP : QEMU_MADV_DONTDUMP)) { + warn_report("Couldn't change property 'dump' on '%s': %s", + object_get_typename(obj), strerror(errno)); + } backend->dump = value; } } @@ -337,11 +344,15 @@ host_memory_backend_memory_complete(UserCreatable *uc, Error **errp) ptr = memory_region_get_ram_ptr(&backend->mr); sz = memory_region_size(&backend->mr); - if (backend->merge) { - qemu_madvise(ptr, sz, QEMU_MADV_MERGEABLE); + if (backend->merge && + qemu_madvise(ptr, sz, QEMU_MADV_MERGEABLE)) { + warn_report("Couldn't set property 'merge' on '%s': %s", + object_get_typename(OBJECT(uc)), strerror(errno)); } - if (!backend->dump) { - qemu_madvise(ptr, sz, QEMU_MADV_DONTDUMP); + if (!backend->dump && + qemu_madvise(ptr, sz, QEMU_MADV_DONTDUMP)) { + warn_report("Couldn't set property 'dump' on '%s': %s", + object_get_typename(OBJECT(uc)), strerror(errno)); } #ifdef CONFIG_NUMA unsigned long lastbit = find_last_bit(backend->host_nodes, MAX_NODES); From patchwork Tue May 28 16:15:09 2024 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Michal Privoznik X-Patchwork-Id: 1940641 Return-Path: X-Original-To: incoming@patchwork.ozlabs.org Delivered-To: patchwork-incoming@legolas.ozlabs.org Authentication-Results: legolas.ozlabs.org; dkim=pass (1024-bit key; unprotected) header.d=redhat.com header.i=@redhat.com header.a=rsa-sha256 header.s=mimecast20190719 header.b=GkRYAmbQ; dkim-atps=neutral Authentication-Results: legolas.ozlabs.org; spf=pass (sender SPF authorized) smtp.mailfrom=nongnu.org (client-ip=209.51.188.17; helo=lists.gnu.org; envelope-from=qemu-devel-bounces+incoming=patchwork.ozlabs.org@nongnu.org; receiver=patchwork.ozlabs.org) Received: from lists.gnu.org (lists.gnu.org [209.51.188.17]) (using TLSv1.2 with cipher ECDHE-ECDSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by legolas.ozlabs.org (Postfix) with ESMTPS id 4Vpd1T2G2cz20f5 for ; Wed, 29 May 2024 02:16:28 +1000 (AEST) Received: from localhost ([::1] helo=lists1p.gnu.org) by lists.gnu.org with esmtp (Exim 4.90_1) (envelope-from ) id 1sBzTw-0003Tp-Gj; 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Tue, 28 May 2024 12:15:18 -0400 X-MC-Unique: Q6iOy824MzGkPufIyvQsyw-1 Received: from smtp.corp.redhat.com (int-mx08.intmail.prod.int.rdu2.redhat.com [10.11.54.8]) (using TLSv1.3 with cipher TLS_AES_256_GCM_SHA384 (256/256 bits) key-exchange X25519 server-signature RSA-PSS (2048 bits) server-digest SHA256) (No client certificate requested) by mimecast-mx02.redhat.com (Postfix) with ESMTPS id 528BE185A780 for ; Tue, 28 May 2024 16:15:18 +0000 (UTC) Received: from maggie.brq.redhat.com (unknown [10.43.3.102]) by smtp.corp.redhat.com (Postfix) with ESMTP id 7FD73C15BC3; Tue, 28 May 2024 16:15:17 +0000 (UTC) From: Michal Privoznik To: qemu-devel@nongnu.org Cc: david@redhat.com, imammedo@redhat.com Subject: [PATCH 3/3] backends/hostmem: Round up memory size for qemu_madvise() and mbind() Date: Tue, 28 May 2024 18:15:09 +0200 Message-ID: In-Reply-To: References: MIME-Version: 1.0 X-Scanned-By: MIMEDefang 3.4.1 on 10.11.54.8 Received-SPF: pass client-ip=170.10.129.124; envelope-from=mprivozn@redhat.com; helo=us-smtp-delivery-124.mimecast.com X-Spam_score_int: -20 X-Spam_score: -2.1 X-Spam_bar: -- X-Spam_report: (-2.1 / 5.0 requ) BAYES_00=-1.9, DKIMWL_WL_HIGH=-0.034, DKIM_SIGNED=0.1, DKIM_VALID=-0.1, DKIM_VALID_AU=-0.1, DKIM_VALID_EF=-0.1, RCVD_IN_DNSWL_NONE=-0.0001, RCVD_IN_MSPIKE_H4=0.001, RCVD_IN_MSPIKE_WL=0.001, SPF_HELO_NONE=0.001, SPF_PASS=-0.001, T_SCC_BODY_TEXT_LINE=-0.01 autolearn=ham autolearn_force=no X-Spam_action: no action X-BeenThere: qemu-devel@nongnu.org X-Mailman-Version: 2.1.29 Precedence: list List-Id: List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Errors-To: qemu-devel-bounces+incoming=patchwork.ozlabs.org@nongnu.org Sender: qemu-devel-bounces+incoming=patchwork.ozlabs.org@nongnu.org Simple reproducer: qemu.git $ ./build/qemu-system-x86_64 \ -m size=8389632k,slots=16,maxmem=25600000k \ -object '{"qom-type":"memory-backend-file","id":"ram-node0","mem-path":"/hugepages2M/","prealloc":true,"size":8590983168,"host-nodes":[0],"policy":"bind"}' \ -numa node,nodeid=0,cpus=0,memdev=ram-node0 With current master I get: qemu-system-x86_64: cannot bind memory to host NUMA nodes: Invalid argument The problem is that memory size (8193MiB) is not an integer multiple of underlying pagesize (2MiB) which triggers a check inside of mbind(), since we can't really set policy just to a fraction of a page. As qemu_madvise() has the same expectation, round size passed to underlying pagesize. Signed-off-by: Michal Privoznik --- backends/hostmem.c | 11 +++++++++++ 1 file changed, 11 insertions(+) diff --git a/backends/hostmem.c b/backends/hostmem.c index 1a6fd1c714..9b727699f6 100644 --- a/backends/hostmem.c +++ b/backends/hostmem.c @@ -179,6 +179,8 @@ static void host_memory_backend_set_merge(Object *obj, bool value, Error **errp) void *ptr = memory_region_get_ram_ptr(&backend->mr); uint64_t sz = memory_region_size(&backend->mr); + sz = ROUND_UP(sz, qemu_ram_pagesize(backend->mr.ram_block)); + if (qemu_madvise(ptr, sz, value ? QEMU_MADV_MERGEABLE : QEMU_MADV_UNMERGEABLE)) { warn_report("Couldn't change property 'merge' on '%s': %s", @@ -208,6 +210,8 @@ static void host_memory_backend_set_dump(Object *obj, bool value, Error **errp) void *ptr = memory_region_get_ram_ptr(&backend->mr); uint64_t sz = memory_region_size(&backend->mr); + sz = ROUND_UP(sz, qemu_ram_pagesize(backend->mr.ram_block)); + if (qemu_madvise(ptr, sz, value ? QEMU_MADV_DODUMP : QEMU_MADV_DONTDUMP)) { warn_report("Couldn't change property 'dump' on '%s': %s", @@ -344,6 +348,13 @@ host_memory_backend_memory_complete(UserCreatable *uc, Error **errp) ptr = memory_region_get_ram_ptr(&backend->mr); sz = memory_region_size(&backend->mr); + /* + * Round up size to be an integer multiple of pagesize, because + * both madvise() and mbind() does not really like setting + * advice/policy to just a fraction of a page. + */ + sz = ROUND_UP(sz, qemu_ram_pagesize(backend->mr.ram_block)); + if (backend->merge && qemu_madvise(ptr, sz, QEMU_MADV_MERGEABLE)) { warn_report("Couldn't set property 'merge' on '%s': %s",