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 A4382C10F1A for ; Tue, 7 May 2024 09:42:51 +0000 (UTC) Received: from gabe.freedesktop.org (localhost [127.0.0.1]) by gabe.freedesktop.org (Postfix) with ESMTP id 25BD710E42B; Tue, 7 May 2024 09:42:51 +0000 (UTC) Authentication-Results: gabe.freedesktop.org; dkim=pass (2048-bit key; unprotected) header.d=intel.com header.i=@intel.com header.b="dwPwkcWz"; dkim-atps=neutral Received: from mgamail.intel.com (mgamail.intel.com [198.175.65.12]) by gabe.freedesktop.org (Postfix) with ESMTPS id 1998010E42B for ; Tue, 7 May 2024 09:42:49 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=intel.com; i=@intel.com; q=dns/txt; s=Intel; t=1715074970; x=1746610970; h=message-id:date:mime-version:subject:from:to:cc: references:in-reply-to; bh=KmlleweDs0U4nUfHCGjLe6NmtCtk/pny6xd+bfpDW5c=; b=dwPwkcWz0y+qVWjYSk4h+GflTamRDsweCTQaPi4siDpdY8G3w+qlu4+n kNQ3G757pFpg3yPdj8ijWNJcgz9xWInQQwC4pJITveDnO8flVeGgfO2BK BCWu9sioIVW59hfoLJ29zXeg+F2/ERurn4r2s6JFgOFRLaaB3o2d3PI5h 8RZZSWZNNuewZ8hKa2EqIrRzj7XDfpW6ho9bm36EciukKw0JwvVOhQUYZ 7FH/Zyo0xWuaMoMSi5UNuyD0De5O4KLtYLFXAUTSR/25rqN8KRZ552FNH 2Ur5FhTEqz9lgGbSIksO/iE2Zudlydz6EEHQdoPFcUeziezXh1PRJChPe w==; X-CSE-ConnectionGUID: 4Rz5fzMhSc6yNnpdpJy9sQ== X-CSE-MsgGUID: 8vJNV/ubTESrpK12Zy6wug== X-IronPort-AV: E=McAfee;i="6600,9927,11065"; a="22270561" X-IronPort-AV: E=Sophos;i="6.07,260,1708416000"; d="scan'208,217";a="22270561" Received: from orviesa008.jf.intel.com ([10.64.159.148]) by orvoesa104.jf.intel.com with ESMTP/TLS/ECDHE-RSA-AES256-GCM-SHA384; 07 May 2024 02:42:49 -0700 X-CSE-ConnectionGUID: NvrJconST4eUf9frPAYgFw== X-CSE-MsgGUID: 5XPkFI8YQrW6sx3r182uPA== X-ExtLoop1: 1 X-IronPort-AV: E=Sophos;i="6.07,260,1708416000"; d="scan'208,217";a="29047158" Received: from nirmoyda-mobl.ger.corp.intel.com (HELO [10.246.32.254]) ([10.246.32.254]) by orviesa008-auth.jf.intel.com with ESMTP/TLS/ECDHE-RSA-AES256-GCM-SHA384; 07 May 2024 02:42:49 -0700 Content-Type: multipart/alternative; boundary="------------jKw4JnHyLKgubk0AeZQDaOYt" Message-ID: <96b6a562-eeaf-49f9-9ade-d58fb061086d@linux.intel.com> Date: Tue, 7 May 2024 11:42:46 +0200 MIME-Version: 1.0 User-Agent: Mozilla Thunderbird Subject: Re: [PATCH] drm/xe: Fix UBSAN shift-out-of-bounds failure From: Nirmoy Das To: Shuicheng Lin , intel-xe@lists.freedesktop.org Cc: Matthew Brost References: <20240507080456.613786-1-shuicheng.lin@intel.com> <2a9a7bb2-c74d-44fb-b9d2-cbb42e462d0f@linux.intel.com> Content-Language: en-US In-Reply-To: <2a9a7bb2-c74d-44fb-b9d2-cbb42e462d0f@linux.intel.com> 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" This is a multi-part message in MIME format. --------------jKw4JnHyLKgubk0AeZQDaOYt Content-Type: text/plain; charset=UTF-8; format=flowed Content-Transfer-Encoding: 7bit On 5/7/2024 11:39 AM, Nirmoy Das wrote: > > > On 5/7/2024 10:04 AM, Shuicheng Lin wrote: >> Here is the failure stack: >> [ 12.988209] ------------[ cut here ]------------ >> [ 12.988216] UBSAN: shift-out-of-bounds in ./include/linux/log2.h:57:13 >> [ 12.988232] shift exponent 64 is too large for 64-bit type 'long unsigned int' >> [ 12.988235] CPU: 4 PID: 1310 Comm: gnome-shell Tainted: G U 6.9.0-rc6+prerelease1158+ #19 >> [ 12.988237] Hardware name: Intel Corporation Raptor Lake Client Platform/RPL-S ADP-S DDR5 UDIMM CRB, BIOS RPLSFWI1.R00.3301.A02.2208050712 08/05/2022 >> [ 12.988239] Call Trace: >> [ 12.988240] >> [ 12.988242] dump_stack_lvl+0xd7/0xf0 >> [ 12.988248] dump_stack+0x10/0x20 >> [ 12.988250] ubsan_epilogue+0x9/0x40 >> [ 12.988253] __ubsan_handle_shift_out_of_bounds+0x10e/0x170 >> [ 12.988260] dma_resv_reserve_fences.cold+0x2b/0x48 >> [ 12.988262] ? ww_mutex_lock_interruptible+0x3c/0x110 >> [ 12.988267] drm_exec_prepare_obj+0x45/0x60 [drm_exec] >> [ 12.988271] ? vm_bind_ioctl_ops_execute+0x5b/0x740 [xe] >> [ 12.988345] vm_bind_ioctl_ops_execute+0x78/0x740 [xe] >> >> It is caused by the value 0 of parameter num_fences in function drm_exec_prepare_obj. >> And lead to in function __rounddown_pow_of_two, "0 - 1" causes the shift-out-of-bounds. >> For the num_fences, it should be 1 at least. >> >> Cc: Matthew Brost >> Signed-off-by: Shuicheng Lin >> --- >> drivers/gpu/drm/xe/xe_vm.c | 4 ++-- >> 1 file changed, 2 insertions(+), 2 deletions(-) >> >> diff --git a/drivers/gpu/drm/xe/xe_vm.c b/drivers/gpu/drm/xe/xe_vm.c >> index d17192c8b7de..96cb4d9762a3 100644 >> --- a/drivers/gpu/drm/xe/xe_vm.c >> +++ b/drivers/gpu/drm/xe/xe_vm.c >> @@ -2692,7 +2692,7 @@ static int vma_lock_and_validate(struct drm_exec *exec, struct xe_vma *vma, >> >> if (bo) { >> if (!bo->vm) >> - err = drm_exec_prepare_obj(exec, &bo->ttm.base, 0); >> + err = drm_exec_prepare_obj(exec, &bo->ttm.base, 1); > > This needs to be fixed in drm_exec_prepare_obj() by checking > num_fences and not calling dma_resv_reserve_fences() > or just call drm_exec_lock_obj() here. ref: https://patchwork.freedesktop.org/patch/577487/ Nirmoy > > Regards, > > Nirmoy > >> if (!err && validate) >> err = xe_bo_validate(bo, xe_vma_vm(vma), true); >> } >> @@ -2777,7 +2777,7 @@ static int vm_bind_ioctl_ops_lock_and_prep(struct drm_exec *exec, >> struct xe_vma_op *op; >> int err; >> >> - err = drm_exec_prepare_obj(exec, xe_vm_obj(vm), 0); >> + err = drm_exec_prepare_obj(exec, xe_vm_obj(vm), 1); >> if (err) >> return err; >> --------------jKw4JnHyLKgubk0AeZQDaOYt Content-Type: text/html; charset=UTF-8 Content-Transfer-Encoding: 7bit


On 5/7/2024 11:39 AM, Nirmoy Das wrote:


On 5/7/2024 10:04 AM, Shuicheng Lin wrote:
Here is the failure stack:
[   12.988209] ------------[ cut here ]------------
[   12.988216] UBSAN: shift-out-of-bounds in ./include/linux/log2.h:57:13
[   12.988232] shift exponent 64 is too large for 64-bit type 'long unsigned int'
[   12.988235] CPU: 4 PID: 1310 Comm: gnome-shell Tainted: G     U             6.9.0-rc6+prerelease1158+ #19
[   12.988237] Hardware name: Intel Corporation Raptor Lake Client Platform/RPL-S ADP-S DDR5 UDIMM CRB, BIOS RPLSFWI1.R00.3301.A02.2208050712 08/05/2022
[   12.988239] Call Trace:
[   12.988240]  <TASK>
[   12.988242]  dump_stack_lvl+0xd7/0xf0
[   12.988248]  dump_stack+0x10/0x20
[   12.988250]  ubsan_epilogue+0x9/0x40
[   12.988253]  __ubsan_handle_shift_out_of_bounds+0x10e/0x170
[   12.988260]  dma_resv_reserve_fences.cold+0x2b/0x48
[   12.988262]  ? ww_mutex_lock_interruptible+0x3c/0x110
[   12.988267]  drm_exec_prepare_obj+0x45/0x60 [drm_exec]
[   12.988271]  ? vm_bind_ioctl_ops_execute+0x5b/0x740 [xe]
[   12.988345]  vm_bind_ioctl_ops_execute+0x78/0x740 [xe]

It is caused by the value 0 of parameter num_fences in function drm_exec_prepare_obj.
And lead to in function __rounddown_pow_of_two, "0 - 1" causes the shift-out-of-bounds.
For the num_fences, it should be 1 at least.

Cc: Matthew Brost <matthew.brost@intel.com>
Signed-off-by: Shuicheng Lin <shuicheng.lin@intel.com>
---
 drivers/gpu/drm/xe/xe_vm.c | 4 ++--
 1 file changed, 2 insertions(+), 2 deletions(-)

diff --git a/drivers/gpu/drm/xe/xe_vm.c b/drivers/gpu/drm/xe/xe_vm.c
index d17192c8b7de..96cb4d9762a3 100644
--- a/drivers/gpu/drm/xe/xe_vm.c
+++ b/drivers/gpu/drm/xe/xe_vm.c
@@ -2692,7 +2692,7 @@ static int vma_lock_and_validate(struct drm_exec *exec, struct xe_vma *vma,
 
 	if (bo) {
 		if (!bo->vm)
-			err = drm_exec_prepare_obj(exec, &bo->ttm.base, 0);
+			err = drm_exec_prepare_obj(exec, &bo->ttm.base, 1);

This needs to be fixed in drm_exec_prepare_obj() by checking num_fences and not calling dma_resv_reserve_fences()

or just call drm_exec_lock_obj() here. ref: https://patchwork.freedesktop.org/patch/577487/

Nirmoy


Regards,

Nirmoy

 		if (!err && validate)
 			err = xe_bo_validate(bo, xe_vma_vm(vma), true);
 	}
@@ -2777,7 +2777,7 @@ static int vm_bind_ioctl_ops_lock_and_prep(struct drm_exec *exec,
 	struct xe_vma_op *op;
 	int err;
 
-	err = drm_exec_prepare_obj(exec, xe_vm_obj(vm), 0);
+	err = drm_exec_prepare_obj(exec, xe_vm_obj(vm), 1);
 	if (err)
 		return err;
--------------jKw4JnHyLKgubk0AeZQDaOYt--