From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from foss.arm.com (foss.arm.com [217.140.110.172]) by smtp.subspace.kernel.org (Postfix) with ESMTP id 3BF0D3B38A9 for ; Wed, 24 Jun 2026 15:34:56 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.client-ip=217.140.110.172 ARC-Seal:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1782315298; cv=none; b=ArBq+flc5CYUiCnstauWgv0B2y6Kwah2+etEf67bzy7XNErontenWvcUQf94McJeVX40CL74BvBP/UQzyyAGQeVBV3eDQzK/3LYSGbUgO2gaZFtr35up/KRhkARff4HjhCab5qnfzfr6Qse+c4wrSLN4zqNKvNT/l4OMp5Y9O98= ARC-Message-Signature:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1782315298; c=relaxed/simple; bh=8MbUdECE7vtm2+3ukK2M86Rfe7gaoQ5YuHIyq3drERg=; h=Message-ID:Date:MIME-Version:Subject:To:Cc:References:From: In-Reply-To:Content-Type; b=IKufiRZQGimkdEhAtgG28Ty9kNwQUdGbuMJvMso3XwGdmSyO/SXhDdXA4TctoueaX2vyqyV0mPLTqorGa2ZDLJmbqdijvMmBdOvVERHWBAlSEDGZSThJHDgp6RkAI4nUvtAQCM1oOgTLH91d7Zhk2qyXIFnuIe8yWmYSsBLPgxs= ARC-Authentication-Results:i=1; smtp.subspace.kernel.org; dmarc=pass (p=none dis=none) header.from=arm.com; spf=pass smtp.mailfrom=arm.com; dkim=pass (1024-bit key) header.d=arm.com header.i=@arm.com header.b=sHs/yrnX; arc=none smtp.client-ip=217.140.110.172 Authentication-Results: smtp.subspace.kernel.org; dmarc=pass (p=none dis=none) header.from=arm.com Authentication-Results: smtp.subspace.kernel.org; spf=pass smtp.mailfrom=arm.com Authentication-Results: smtp.subspace.kernel.org; dkim=pass (1024-bit key) header.d=arm.com header.i=@arm.com header.b="sHs/yrnX" Received: from usa-sjc-imap-foss1.foss.arm.com (unknown [10.121.207.14]) by usa-sjc-mx-foss1.foss.arm.com (Postfix) with ESMTP id C8E7E25E1; Wed, 24 Jun 2026 08:34:51 -0700 (PDT) Received: from [10.57.80.146] (unknown [10.57.80.146]) by usa-sjc-imap-foss1.foss.arm.com (Postfix) with ESMTPSA id 8DE0B3F905; Wed, 24 Jun 2026 08:34:53 -0700 (PDT) DKIM-Signature: v=1; a=rsa-sha256; c=simple/simple; d=arm.com; s=foss; t=1782315296; bh=8MbUdECE7vtm2+3ukK2M86Rfe7gaoQ5YuHIyq3drERg=; h=Date:Subject:To:Cc:References:From:In-Reply-To:From; b=sHs/yrnXAFcD3Ti+VgtyyEOF+UIy4qMqQx+ZzHYLwdjJUI+Lh/j1YH/cfwy1sR5n4 qNE8iWVmtlEBRZEwBsMpPmRs/vGQWoib8zqUt6hDjZRM33/BnP6POGuDsXp7sCyLhi VQrqzANPlK2d5HKpK2mUQdWtxeLIvqmXwstdplyU= Message-ID: Date: Wed, 24 Jun 2026 16:34:51 +0100 Precedence: bulk X-Mailing-List: linux-kernel@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 User-Agent: Mozilla Thunderbird Subject: Re: [PATCH] drm/panthor: Check VMA boundaries for PMD mappings To: "Christian A. Ehrhardt" , Boris Brezillon , dri-devel@lists.freedesktop.org Cc: Liviu Dudau , Andrew Morton , Maarten Lankhorst , Maxime Ripard , Thomas Zimmermann , David Airlie , Simona Vetter , linux-mm@kvack.org, linux-kernel@vger.kernel.org References: <20260623181942.1536598-1-lk@c--e.de> From: Steven Price Content-Language: en-GB In-Reply-To: <20260623181942.1536598-1-lk@c--e.de> Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 7bit On 23/06/2026 19:19, Christian A. Ehrhardt wrote: > When checking a different patch[1] sashiko AI pointed out that > panthor needs the same fix[2]: > > In the ->huge_fault handler do not install a PMD huge page > mapping if the huge page exceeds the boundaries of the VMA. > > [1] https://lore.kernel.org/lkml/20260622215718.1532689-1-lk@c--e.de/ > [2] https://sashiko.dev/#/patchset/20260622215718.1532689-1-lk%40c--e.de > > Cc: Boris Brezillon > Cc: Steven Price > Cc: Liviu Dudau > Fixes: 68cbf96b1e9b ("drm/panthor: Part ways with drm_gem_shmem_object") > Signed-off-by: Christian A. Ehrhardt Reviewed-by: Steven Price > --- > drivers/gpu/drm/panthor/panthor_gem.c | 6 +++++- > 1 file changed, 5 insertions(+), 1 deletion(-) > > NOTE: > The panthor version is only compile tested because I don't > have the hardware. However, the code is identical to that > fixed in [1] and I have a reproducer for that. > > No need for for stable backports. The code is new in 7.1. > > diff --git a/drivers/gpu/drm/panthor/panthor_gem.c b/drivers/gpu/drm/panthor/panthor_gem.c > index a1e2eb1ca7bb..54535bae2b0c 100644 > --- a/drivers/gpu/drm/panthor/panthor_gem.c > +++ b/drivers/gpu/drm/panthor/panthor_gem.c > @@ -802,9 +802,13 @@ static vm_fault_t insert_page(struct vm_fault *vmf, unsigned int order, struct p > } else if (order == PMD_ORDER) { > unsigned long pfn = page_to_pfn(page); > unsigned long paddr = pfn << PAGE_SHIFT; > + struct vm_area_struct *vma = vmf->vma; > + unsigned long start = ALIGN_DOWN(vmf->address, PMD_SIZE); > + unsigned long end = start + PMD_SIZE; > + bool in_range = vma->vm_start <= start && end <= vma->vm_end; > bool aligned = (vmf->address & ~PMD_MASK) == (paddr & ~PMD_MASK); > > - if (aligned && > + if (aligned && in_range && > folio_test_pmd_mappable(page_folio(page))) { > pfn &= PMD_MASK >> PAGE_SHIFT; > return vmf_insert_pfn_pmd(vmf, pfn, vmf->flags & FAULT_FLAG_WRITE);