From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: X-Spam-Checker-Version: SpamAssassin 3.4.0 (2014-02-07) on aws-us-west-2-korg-lkml-1.web.codeaurora.org Received: from gabe.freedesktop.org (gabe.freedesktop.org [131.252.210.177]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by smtp.lore.kernel.org (Postfix) with ESMTPS id E86E6E9A03B for ; Thu, 19 Feb 2026 09:13:41 +0000 (UTC) Received: from gabe.freedesktop.org (localhost [127.0.0.1]) by gabe.freedesktop.org (Postfix) with ESMTP id A6A1C10E6A1; Thu, 19 Feb 2026 09:13:41 +0000 (UTC) Authentication-Results: gabe.freedesktop.org; dkim=pass (2048-bit key; unprotected) header.d=intel.com header.i=@intel.com header.b="hU/uOIAB"; dkim-atps=neutral Received: from mgamail.intel.com (mgamail.intel.com [192.198.163.14]) by gabe.freedesktop.org (Postfix) with ESMTPS id B3FDC10E69E for ; Thu, 19 Feb 2026 09:13:37 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=intel.com; i=@intel.com; q=dns/txt; s=Intel; t=1771492417; x=1803028417; h=from:to:cc:subject:date:message-id:in-reply-to: references:mime-version:content-transfer-encoding; bh=fg+rBC1/FFtu0xh5Cb+Lu/w3H1gyg7HvioMD6I5oyEg=; b=hU/uOIABBPPU2T+w3uRue75//6Jq3XnWdPnyVaBJtslvPexI3HKi4BO3 RbwAOa3CKKCEwh8B2qnJgm8cq8X/y+47yshoVeSOuvASF61xsxAZWnBAg axJYIPACBNRKLLUhHSl39wCaxOiqs/o7tE6FCSUQQgEBLWFmcK8P5JmIZ xP4XN8rr0kAu0knvmqUz2Z8RLVKj8BeJ5TgHm1jMN3Qo/IQryf3bPSEVJ 3VkKUJncnmq01hqvordP9NpWOZILKK9S4GVqfhvEd0Flk/v+97Rh5q0uI XMvvuqCj3j5IYlJ94MXEglEgaosVrGrtd5qBPQ9Wq2BNNka07cNihojK/ A==; X-CSE-ConnectionGUID: IlgF93XzTiGvtyTNTftGvQ== X-CSE-MsgGUID: DOfOkCGLQHOcpsH/9VkgSw== X-IronPort-AV: E=McAfee;i="6800,10657,11705"; a="72637317" X-IronPort-AV: E=Sophos;i="6.21,299,1763452800"; d="scan'208";a="72637317" Received: from fmviesa003.fm.intel.com ([10.60.135.143]) by fmvoesa108.fm.intel.com with ESMTP/TLS/ECDHE-RSA-AES256-GCM-SHA384; 19 Feb 2026 01:13:37 -0800 X-CSE-ConnectionGUID: tASphlgHTkGXb/Qn0ExzuA== X-CSE-MsgGUID: XJ2BOWphS1uqxfcohudQow== X-ExtLoop1: 1 Received: from varungup-desk.iind.intel.com ([10.190.238.71]) by fmviesa003-auth.fm.intel.com with ESMTP/TLS/ECDHE-RSA-AES256-GCM-SHA384; 19 Feb 2026 01:13:36 -0800 From: Arvind Yadav To: intel-xe@lists.freedesktop.org Cc: matthew.brost@intel.com, himal.prasad.ghimiray@intel.com, thomas.hellstrom@linux.intel.com Subject: [RFC 7/7] drm/xe/svm: Correct memory attribute reset for partial unmap Date: Thu, 19 Feb 2026 14:43:12 +0530 Message-ID: <20260219091312.796749-8-arvind.yadav@intel.com> X-Mailer: git-send-email 2.43.0 In-Reply-To: <20260219091312.796749-1-arvind.yadav@intel.com> References: <20260219091312.796749-1-arvind.yadav@intel.com> MIME-Version: 1.0 Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 8bit X-BeenThere: intel-xe@lists.freedesktop.org X-Mailman-Version: 2.1.29 Precedence: list List-Id: Intel Xe graphics driver List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Errors-To: intel-xe-bounces@lists.freedesktop.org Sender: "Intel-xe" From: Himal Prasad Ghimiray When performing a partial unmap of an SVM range, the memory attributes were being reset for the entire range instead of just the portion being unmapped. This could lead to unintended side effects and behaviour. Fix this by restricting the attribute reset to only the affected subrange that is being unmapped. Cc: Matthew Brost Cc: Thomas Hellström Signed-off-by: Himal Prasad Ghimiray Signed-off-by: Arvind Yadav --- drivers/gpu/drm/xe/xe_svm.c | 56 +++++++++++++++++++++++++++---------- drivers/gpu/drm/xe/xe_svm.h | 10 +++++++ 2 files changed, 52 insertions(+), 14 deletions(-) diff --git a/drivers/gpu/drm/xe/xe_svm.c b/drivers/gpu/drm/xe/xe_svm.c index 8335fdc976b5..3c833e6d6b2c 100644 --- a/drivers/gpu/drm/xe/xe_svm.c +++ b/drivers/gpu/drm/xe/xe_svm.c @@ -57,6 +57,8 @@ void *xe_svm_private_page_owner(struct xe_vm *vm, bool force_smem) return force_smem ? NULL : vm->svm.peer.owner; } +#define XE_SVM_ATTR_RETRY_MAX 3 + static bool xe_svm_range_in_vram(struct xe_svm_range *range) { /* @@ -126,15 +128,23 @@ static void xe_svm_range_free(struct drm_gpusvm_range *range) kfree(range); } +static void xe_svm_range_set_unmapped(struct xe_svm_range *range, + const struct mmu_notifier_range *mmu_range) +{ + drm_gpusvm_range_set_unmapped(&range->base, mmu_range); + if (range->base.pages.flags.partial_unmap) { + range->partial_unmap.start = max(xe_svm_range_start(range), mmu_range->start); + range->partial_unmap.end = min(xe_svm_range_end(range), mmu_range->end); + } +} + static void xe_svm_garbage_collector_add_range(struct xe_vm *vm, struct xe_svm_range *range, const struct mmu_notifier_range *mmu_range) { struct xe_device *xe = vm->xe; - range_debug(range, "GARBAGE COLLECTOR ADD"); - - drm_gpusvm_range_set_unmapped(&range->base, mmu_range); + xe_svm_range_set_unmapped(range, mmu_range); spin_lock(&vm->svm.garbage_collector.lock); if (list_empty(&range->garbage_collector_link)) @@ -375,9 +385,10 @@ static int xe_svm_range_set_default_attr(struct xe_vm *vm, u64 start, u64 end) static int xe_svm_garbage_collector(struct xe_vm *vm) { struct xe_svm_range *range; - u64 range_start; - u64 range_end; + u64 unmap_start; + u64 unmap_end; int err, ret = 0; + int retry_count; lockdep_assert_held_write(&vm->lock); @@ -392,8 +403,13 @@ static int xe_svm_garbage_collector(struct xe_vm *vm) if (!range) break; - range_start = xe_svm_range_start(range); - range_end = xe_svm_range_end(range); + if (range->base.pages.flags.partial_unmap) { + unmap_start = range->partial_unmap.start; + unmap_end = range->partial_unmap.end; + } else { + unmap_start = xe_svm_range_start(range); + unmap_end = xe_svm_range_end(range); + } list_del(&range->garbage_collector_link); spin_unlock(&vm->svm.garbage_collector.lock); @@ -407,13 +423,25 @@ static int xe_svm_garbage_collector(struct xe_vm *vm) return err; } - err = xe_svm_range_set_default_attr(vm, range_start, range_end); - if (err) { - if (err == -EAGAIN) - ret = -EAGAIN; - else - return err; - } + /* + * Retry set_default_attr on -EAGAIN (VMA was recreated). + * Limit retries to prevent infinite loop. + */ + retry_count = 0; + + do { + err = xe_svm_range_set_default_attr(vm, unmap_start, unmap_end); + if (err == -EAGAIN && ++retry_count > XE_SVM_ATTR_RETRY_MAX) { + drm_err(&vm->xe->drm, + "SET_ATTR retry limit exceeded for [0x%llx-0x%llx]\n", + unmap_start, unmap_end); + xe_vm_kill(vm, true); + return -EIO; + } + } while (err == -EAGAIN); + + if (err) + return err; } spin_unlock(&vm->svm.garbage_collector.lock); diff --git a/drivers/gpu/drm/xe/xe_svm.h b/drivers/gpu/drm/xe/xe_svm.h index b7b8eeacf196..4651e044cf53 100644 --- a/drivers/gpu/drm/xe/xe_svm.h +++ b/drivers/gpu/drm/xe/xe_svm.h @@ -46,6 +46,16 @@ struct xe_svm_range { * range. Protected by GPU SVM notifier lock. */ u8 tile_invalidated; + /** + * @partial_unmap: Structure to hold partial unmap range info. + * Valid only if partial unmap is in effect. + */ + struct { + /** @start: Start address of the partial unmap range */ + u64 start; + /** @end: End address of the partial unmap range */ + u64 end; + } partial_unmap; }; /** -- 2.43.0