{"id":2229253,"url":"http://patchwork.ozlabs.org/api/1.1/patches/2229253/?format=json","web_url":"http://patchwork.ozlabs.org/project/linux-pwm/patch/20260427221155.2144848-23-dakr@kernel.org/","project":{"id":38,"url":"http://patchwork.ozlabs.org/api/1.1/projects/38/?format=json","name":"Linux PWM development","link_name":"linux-pwm","list_id":"linux-pwm.vger.kernel.org","list_email":"linux-pwm@vger.kernel.org","web_url":"","scm_url":"","webscm_url":""},"msgid":"<20260427221155.2144848-23-dakr@kernel.org>","date":"2026-04-27T22:11:20","name":"[REF,22/24] gpu: nova-core: unregister sysmem flush page from Drop","commit_ref":null,"pull_url":null,"state":"handled-elsewhere","archived":false,"hash":"bdb43387f4f018fd07d778e8380b9cd14b5fb02a","submitter":{"id":89037,"url":"http://patchwork.ozlabs.org/api/1.1/people/89037/?format=json","name":"Danilo Krummrich","email":"dakr@kernel.org"},"delegate":null,"mbox":"http://patchwork.ozlabs.org/project/linux-pwm/patch/20260427221155.2144848-23-dakr@kernel.org/mbox/","series":[{"id":501734,"url":"http://patchwork.ozlabs.org/api/1.1/series/501734/?format=json","web_url":"http://patchwork.ozlabs.org/project/linux-pwm/list/?series=501734","date":"2026-04-27T22:10:58","name":"rust: device: Higher-Ranked Lifetime Types for device drivers","version":1,"mbox":"http://patchwork.ozlabs.org/series/501734/mbox/"}],"comments":"http://patchwork.ozlabs.org/api/patches/2229253/comments/","check":"pending","checks":"http://patchwork.ozlabs.org/api/patches/2229253/checks/","tags":{},"headers":{"Return-Path":"\n ","X-Original-To":["incoming@patchwork.ozlabs.org","linux-pwm@vger.kernel.org"],"Delivered-To":"patchwork-incoming@legolas.ozlabs.org","Authentication-Results":["legolas.ozlabs.org;\n\tdkim=pass (2048-bit key;\n unprotected) header.d=kernel.org header.i=@kernel.org header.a=rsa-sha256\n header.s=k20201202 header.b=BqDRm9LT;\n\tdkim-atps=neutral","legolas.ozlabs.org;\n spf=pass (sender SPF authorized) smtp.mailfrom=vger.kernel.org\n (client-ip=2600:3c0a:e001:db::12fc:5321; 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a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116;\n\tt=1777328067; cv=none;\n b=hmLKQhSJNr5U/BBAmd4pt6SHrXqIpbXz/j2+cA7Ep1hXbM7clvXTH9GvKqWnbFBSS5NSFM9v2/+V3mGwz2dnCocU4ijXdaXHKMs5ByEygFay/b5GhEfVe2UBV0hj7+E9O0w3GSv6pmS8NzBim001G6lMv2rBVZAMB9TUnRF44jA=","ARC-Message-Signature":"i=1; a=rsa-sha256; d=subspace.kernel.org;\n\ts=arc-20240116; t=1777328067; c=relaxed/simple;\n\tbh=hYy8LQDnO+hisbOptHtgqKp36k1YyJTGix7eeoo2qKk=;\n\th=From:To:Cc:Subject:Date:Message-ID:In-Reply-To:References:\n\t MIME-Version;\n b=a7auGlE90LnSGD3byLYli0X76YCfzM3JWJzQXPVV4kDrOMfb++w2Ikzj1EQqRn2AhNPCBzhPDFErpZBFykm/hf+k9PMgyCNb/+GK7TviJQL8/myRmYs+vzycU3k/DSWs7aYzew4qmzj3jDzxynj18laNfhCI+HVEnE/LZ1xsVCU=","ARC-Authentication-Results":"i=1; smtp.subspace.kernel.org;\n dkim=pass (2048-bit key) header.d=kernel.org header.i=@kernel.org\n header.b=BqDRm9LT; arc=none smtp.client-ip=10.30.226.201","DKIM-Signature":"v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org;\n\ts=k20201202; t=1777328067;\n\tbh=hYy8LQDnO+hisbOptHtgqKp36k1YyJTGix7eeoo2qKk=;\n\th=From:To:Cc:Subject:Date:In-Reply-To:References:From;\n\tb=BqDRm9LTAxT+LFyHHIuPW75dzJcoI9Ybx7Pav2R3kJM6ezZK8ghNMm+Vgu0kZDyZK\n\t 1LudCaJgONM+Un6S/kbl7SB8Mcga8LywZ7inQvNuX1KcK7KaSNDiyXC7DBPDVdTKor\n\t 0q2svsR7Us01zcKWz6u/qqn6vkMogrDSopGHpgCW5TGai40EemoNAzP0c0nAQAfQN4\n\t l2N+0gniTfMs4GFNXBcrNGkoZtep7KOXCrc+BN9b5PlcSlhqV7AuaookXi4u61d0b9\n\t TflB5dPw/5CUgL0yAScR61V23nWsROYxBmcBHmPPDz34QgZrIkEkjFfH5hf1xXxnE3\n\t DpmWxroqy3GiQ==","From":"Danilo Krummrich ","To":"gregkh@linuxfoundation.org,\n\trafael@kernel.org,\n\tacourbot@nvidia.com,\n\taliceryhl@google.com,\n\tdavid.m.ertman@intel.com,\n\tira.weiny@intel.com,\n\tleon@kernel.org,\n\tviresh.kumar@linaro.org,\n\tm.wilczynski@samsung.com,\n\tukleinek@kernel.org,\n\tbhelgaas@google.com,\n\tkwilczynski@kernel.org,\n\tabdiel.janulgue@gmail.com,\n\trobin.murphy@arm.com,\n\tmarkus.probst@posteo.de,\n\tojeda@kernel.org,\n\tboqun@kernel.org,\n\tgary@garyguo.net,\n\tbjorn3_gh@protonmail.com,\n\tlossin@kernel.org,\n\ta.hindborg@kernel.org,\n\ttmgross@umich.edu","Cc":"driver-core@lists.linux.dev,\n\tlinux-kernel@vger.kernel.org,\n\tnova-gpu@lists.linux.dev,\n\tdri-devel@lists.freedesktop.org,\n\tlinux-pm@vger.kernel.org,\n\tlinux-pwm@vger.kernel.org,\n\tlinux-pci@vger.kernel.org,\n\trust-for-linux@vger.kernel.org,\n\tDanilo Krummrich ,\n\tEliot Courtney ","Subject":"[PATCH REF 22/24] gpu: nova-core: unregister sysmem flush page from\n Drop","Date":"Tue, 28 Apr 2026 00:11:20 +0200","Message-ID":"<20260427221155.2144848-23-dakr@kernel.org>","X-Mailer":"git-send-email 2.54.0","In-Reply-To":"<20260427221155.2144848-1-dakr@kernel.org>","References":"<20260427221155.2144848-1-dakr@kernel.org>","Precedence":"bulk","X-Mailing-List":"linux-pwm@vger.kernel.org","List-Id":"","List-Subscribe":"","List-Unsubscribe":"","MIME-Version":"1.0","Content-Transfer-Encoding":"8bit"},"content":"Now that SysmemFlush can borrow the Bar via HRT lifetime, store a &'a\nBar0 reference and implement Drop to automatically unregister the\nsysmem flush page. This removes the need for manual unregister() calls\nand the Gpu::unbind() method.\n\nReported-by: Eliot Courtney \nCloses: https://lore.kernel.org/all/20260409-fix-systemflush-v1-1-a1d6c968f17c@nvidia.com/\nFixes: 6554ad65b589 (\"gpu: nova-core: register sysmem flush page\")\nSigned-off-by: Danilo Krummrich \n---\n drivers/gpu/nova-core/driver.rs | 4 ----\n drivers/gpu/nova-core/fb.rs | 22 ++++++++++------------\n drivers/gpu/nova-core/gpu.rs | 9 +--------\n 3 files changed, 11 insertions(+), 24 deletions(-)","diff":"diff --git a/drivers/gpu/nova-core/driver.rs b/drivers/gpu/nova-core/driver.rs\nindex ec9cecb30f63..401ae213991f 100644\n--- a/drivers/gpu/nova-core/driver.rs\n+++ b/drivers/gpu/nova-core/driver.rs\n@@ -111,8 +111,4 @@ fn probe(\n }))\n })\n }\n-\n- fn unbind(_pdev: &'a pci::Device, this: Pin<&'a Self>) {\n- this.gpu.unbind();\n- }\n }\ndiff --git a/drivers/gpu/nova-core/fb.rs b/drivers/gpu/nova-core/fb.rs\nindex bdd5eed760e1..cbc42e98afca 100644\n--- a/drivers/gpu/nova-core/fb.rs\n+++ b/drivers/gpu/nova-core/fb.rs\n@@ -46,21 +46,20 @@\n /// Because of this, the sysmem flush memory page must be registered as early as possible during\n /// driver initialization, and before any falcon is reset.\n ///\n-/// Users are responsible for manually calling [`Self::unregister`] before dropping this object,\n-/// otherwise the GPU might still use it even after it has been freed.\n-pub(crate) struct SysmemFlush {\n+pub(crate) struct SysmemFlush<'a> {\n /// Chipset we are operating on.\n chipset: Chipset,\n device: ARef,\n+ bar: &'a Bar0,\n /// Keep the page alive as long as we need it.\n page: CoherentHandle,\n }\n \n-impl SysmemFlush {\n+impl<'a> SysmemFlush<'a> {\n /// Allocate a memory page and register it as the sysmem flush page.\n pub(crate) fn register(\n dev: &device::Device,\n- bar: &Bar0,\n+ bar: &'a Bar0,\n chipset: Chipset,\n ) -> Result {\n let page = CoherentHandle::alloc(dev, kernel::page::PAGE_SIZE, GFP_KERNEL)?;\n@@ -70,19 +69,18 @@ pub(crate) fn register(\n Ok(Self {\n chipset,\n device: dev.into(),\n+ bar,\n page,\n })\n }\n+}\n \n- /// Unregister the managed sysmem flush page.\n- ///\n- /// In order to gracefully tear down the GPU, users must make sure to call this method before\n- /// dropping the object.\n- pub(crate) fn unregister(&self, bar: &Bar0) {\n+impl Drop for SysmemFlush<'_> {\n+ fn drop(&mut self) {\n let hal = hal::fb_hal(self.chipset);\n \n- if hal.read_sysmem_flush_page(bar) == self.page.dma_handle() {\n- let _ = hal.write_sysmem_flush_page(bar, 0).inspect_err(|e| {\n+ if hal.read_sysmem_flush_page(self.bar) == self.page.dma_handle() {\n+ let _ = hal.write_sysmem_flush_page(self.bar, 0).inspect_err(|e| {\n dev_warn!(\n &self.device,\n \"failed to unregister sysmem flush page: {:?}\\n\",\ndiff --git a/drivers/gpu/nova-core/gpu.rs b/drivers/gpu/nova-core/gpu.rs\nindex 922197f2aeef..ff9a90a46609 100644\n--- a/drivers/gpu/nova-core/gpu.rs\n+++ b/drivers/gpu/nova-core/gpu.rs\n@@ -228,7 +228,7 @@ pub(crate) struct Gpu<'a> {\n bar: &'a Bar0,\n /// System memory page required for flushing all pending GPU-side memory writes done through\n /// PCIE into system memory, via sysmembar (A GPU-initiated HW memory-barrier operation).\n- sysmem_flush: SysmemFlush,\n+ sysmem_flush: SysmemFlush<'a>,\n /// GSP falcon instance, used for GSP boot up and cleanup.\n gsp_falcon: Falcon,\n /// SEC2 falcon instance, used for GSP boot up and cleanup.\n@@ -271,11 +271,4 @@ pub(crate) fn new(\n _: { gsp.boot(pdev, bar, spec.chipset, gsp_falcon, sec2_falcon)? },\n })\n }\n-\n- /// Called when the corresponding [`Device`](device::Device) is unbound.\n- ///\n- /// Note: This method must only be called from `Driver::unbind`.\n- pub(crate) fn unbind(&self) {\n- self.sysmem_flush.unregister(self.bar);\n- }\n }\n","prefixes":["REF","22/24"]}