{"id":2225170,"url":"http://patchwork.ozlabs.org/api/1.1/patches/2225170/?format=json","web_url":"http://patchwork.ozlabs.org/project/qemu-devel/patch/20260420140552.104369-3-eric.auger@redhat.com/","project":{"id":14,"url":"http://patchwork.ozlabs.org/api/1.1/projects/14/?format=json","name":"QEMU Development","link_name":"qemu-devel","list_id":"qemu-devel.nongnu.org","list_email":"qemu-devel@nongnu.org","web_url":"","scm_url":"","webscm_url":""},"msgid":"<20260420140552.104369-3-eric.auger@redhat.com>","date":"2026-04-20T14:03:52","name":"[v10,2/7] target/arm/machine: Handle ToleranceNotOnBothEnds migration tolerances","commit_ref":null,"pull_url":null,"state":"new","archived":false,"hash":"37d61d1465f7974a2a63db8fbd0500cde103b47c","submitter":{"id":69187,"url":"http://patchwork.ozlabs.org/api/1.1/people/69187/?format=json","name":"Eric Auger","email":"eric.auger@redhat.com"},"delegate":null,"mbox":"http://patchwork.ozlabs.org/project/qemu-devel/patch/20260420140552.104369-3-eric.auger@redhat.com/mbox/","series":[{"id":500612,"url":"http://patchwork.ozlabs.org/api/1.1/series/500612/?format=json","web_url":"http://patchwork.ozlabs.org/project/qemu-devel/list/?series=500612","date":"2026-04-20T14:03:52","name":"[v10,1/7] target/arm/cpu: Introduce the infrastructure for cpreg migration tolerances","version":10,"mbox":"http://patchwork.ozlabs.org/series/500612/mbox/"}],"comments":"http://patchwork.ozlabs.org/api/patches/2225170/comments/","check":"pending","checks":"http://patchwork.ozlabs.org/api/patches/2225170/checks/","tags":{},"headers":{"Return-Path":"","X-Original-To":"incoming@patchwork.ozlabs.org","Delivered-To":"patchwork-incoming@legolas.ozlabs.org","Authentication-Results":["legolas.ozlabs.org;\n\tdkim=pass (1024-bit key;\n unprotected) header.d=redhat.com header.i=@redhat.com header.a=rsa-sha256\n header.s=mimecast20190719 header.b=DJ+H5oPS;\n\tdkim-atps=neutral","legolas.ozlabs.org;\n spf=pass (sender SPF authorized) smtp.mailfrom=nongnu.org\n (client-ip=209.51.188.17; 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a=rsa-sha256; c=relaxed/relaxed; d=redhat.com;\n s=mimecast20190719; t=1776693975;\n h=from:from:reply-to:subject:subject:date:date:message-id:message-id:\n to:to:cc:mime-version:mime-version:\n content-transfer-encoding:content-transfer-encoding:\n in-reply-to:in-reply-to:references:references;\n bh=p01fZPFdY51Zmpaz9NyifZyaadu4zisCZRuTPFsPKmk=;\n b=DJ+H5oPSzMyJAM56m8Vi1z7OhEBVDp0M34CrygUnrtp3hCta9F7XzufzFuV1IprNLx6Btl\n x5rKBwm8GJWFZRA3GdFjnHx5vZ9jqDdg7IeepBgZ6D/4fDLtX2Ckc0HacBcXcU5PE8Xv3Z\n h7+17XDyS58zOFlZPiX4kbxuVQzJvhg=","X-MC-Unique":"exluTlvPNZ69tqYtia2L2Q-1","X-Mimecast-MFC-AGG-ID":"exluTlvPNZ69tqYtia2L2Q_1776693969","From":"Eric Auger ","To":"eric.auger.pro@gmail.com, eric.auger@redhat.com, qemu-devel@nongnu.org,\n qemu-arm@nongnu.org, peter.maydell@linaro.org, cohuck@redhat.com,\n sebott@redhat.com, peterx@redhat.com, philmd@linaro.org,\n alex.bennee@linaro.org","Subject":"[PATCH v10 2/7] target/arm/machine: Handle ToleranceNotOnBothEnds\n migration tolerances","Date":"Mon, 20 Apr 2026 16:03:52 +0200","Message-ID":"<20260420140552.104369-3-eric.auger@redhat.com>","In-Reply-To":"<20260420140552.104369-1-eric.auger@redhat.com>","References":"<20260420140552.104369-1-eric.auger@redhat.com>","MIME-Version":"1.0","Content-Transfer-Encoding":"8bit","X-Scanned-By":"MIMEDefang 3.4.1 on 10.30.177.93","Received-SPF":"pass client-ip=170.10.129.124;\n envelope-from=eric.auger@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=-0.001,\n DKIM_SIGNED=0.1, DKIM_VALID=-0.1, DKIM_VALID_AU=-0.1, DKIM_VALID_EF=-0.1,\n RCVD_IN_DNSWL_NONE=-0.0001, RCVD_IN_MSPIKE_H4=0.001, RCVD_IN_MSPIKE_WL=0.001,\n SPF_HELO_PASS=-0.001, SPF_PASS=-0.001 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":"qemu development ","List-Unsubscribe":",\n ","List-Archive":"","List-Post":"","List-Help":"","List-Subscribe":",\n ","Errors-To":"qemu-devel-bounces+incoming=patchwork.ozlabs.org@nongnu.org","Sender":"qemu-devel-bounces+incoming=patchwork.ozlabs.org@nongnu.org"},"content":"If there is a mismatch between the cpreg indexes found on both ends,\ncheck whether a tolerance was registered for the given kvmidx. If any,\nsilence warning/errors.\n\nSigned-off-by: Eric Auger \nReviewed-by: Peter Maydell \n\n---\n\nv9 -> v10\n- s/shall/should\n- remove obsolete desc about helper in commit description\n- Added Peter's R-b\n- Reworded the commit message\n---\n target/arm/machine.c | 21 +++++++++++++++------\n target/arm/trace-events | 2 ++\n 2 files changed, 17 insertions(+), 6 deletions(-)","diff":"diff --git a/target/arm/machine.c b/target/arm/machine.c\nindex b0e499515cf..8a698f601c6 100644\n--- a/target/arm/machine.c\n+++ b/target/arm/machine.c\n@@ -1065,25 +1065,34 @@ static void handle_cpreg_missing_in_incoming_stream(ARMCPU *cpu, uint64_t kvmidx\n {\n g_autofree gchar *name = print_register_name(kvmidx);\n \n+ if (arm_cpu_match_cpreg_mig_tolerance(cpu, kvmidx,\n+ 0, 0, ToleranceNotOnBothEnds)) {\n+ trace_tolerate_cpreg_missing_in_incoming_stream(name);\n+ return;\n+ }\n warn_report(\"%s: %s \"\n \"expected by the destination but not in the incoming stream: \"\n \"skip it\", __func__, name);\n }\n \n /*\n- * Handle the situation where @kvmidx is in the incoming stream\n- * but not on destination. This currently fails the migration but\n- * we plan to accomodate some exceptions, hence the boolean returned value.\n+ * Handle the situation where @kvmidx is in the incoming\n+ * stream but not on destination. This fails the migration if\n+ * no cpreg mig tolerance is matched for this @kvmidx\n+ * Return true if the migration should eventually fail\n */\n static bool handle_cpreg_only_in_incoming_stream(ARMCPU *cpu, uint64_t kvmidx)\n {\n g_autofree gchar *name = print_register_name(kvmidx);\n- bool fail = true;\n \n+ if (arm_cpu_match_cpreg_mig_tolerance(cpu, kvmidx,\n+ 0, 0, ToleranceNotOnBothEnds)) {\n+ trace_tolerate_cpreg_only_in_incoming_stream(name);\n+ return false;\n+ }\n error_report(\"%s: %s in the incoming stream but unknown on the \"\n \"destination: fail migration\", __func__, name);\n-\n- return fail;\n+ return true;\n }\n \n static int cpu_post_load(void *opaque, int version_id)\ndiff --git a/target/arm/trace-events b/target/arm/trace-events\nindex 2de0406f784..8502fb3265c 100644\n--- a/target/arm/trace-events\n+++ b/target/arm/trace-events\n@@ -29,3 +29,5 @@ arm_psci_call(uint64_t x0, uint64_t x1, uint64_t x2, uint64_t x3, uint32_t cpuid\n \n # machine.c\n cpu_post_load(uint32_t cpreg_vmstate_array_len, uint32_t cpreg_array_len) \"cpreg_vmstate_array_len=%d cpreg_array_len=%d\"\n+tolerate_cpreg_missing_in_incoming_stream(char *name) \"%s is missing in incoming stream but this is explicitly tolerated\"\n+tolerate_cpreg_only_in_incoming_stream(char *name) \"%s is in incoming stream but not on destination but this is explicitly tolerated\"\n","prefixes":["v10","2/7"]}