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 2E8BF3597A for ; Fri, 19 Sep 2025 12:14:59 +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=1758284101; cv=none; b=dbQscITXz+IB4O+UcBBcHj7cN2iAJHNlj14KN/tlv/8H48OOjCw+yA5ZVx2R5hiWC+db+mSdqKZFs+d+CQe1rIgoUIOLUXAY1Bx2Oke4PPyQh1wkVQZa/3gCrJay99Qtk5EJvgfauwTMBji859E6h48wOKlEFXFawt85VjXx8UI= ARC-Message-Signature:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1758284101; c=relaxed/simple; bh=+beKHJIQYtWb6UPelOK+FmlPi9FAXTmHnzAxH9jdvmI=; h=Message-ID:Date:MIME-Version:Subject:To:Cc:References:From: In-Reply-To:Content-Type; b=L/Xi6Fc1hlrdAwLZMFGJ7u+B+k7u0fP4FHRYjJCCka57i+PnYsUtC/66wfCnYRP3BMr3CsCRLCYvfrNhim4iZ1fs5bgR8syV0AN4ADDB794tz5cB0ToK1Y7CgH+ZpRWU1GuT85ufrsKda48pRZiQXN3RIDR1+tX5SpG5MAHDAWU= 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; 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 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 27447169C; Fri, 19 Sep 2025 05:14:51 -0700 (PDT) Received: from [10.164.136.41] (unknown [10.164.136.41]) by usa-sjc-imap-foss1.foss.arm.com (Postfix) with ESMTPSA id 9D1F23F673; Fri, 19 Sep 2025 05:14:55 -0700 (PDT) Message-ID: Date: Fri, 19 Sep 2025 17:44:52 +0530 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: [RESEND PATCH v5] arm64: Enable vmalloc-huge with ptdump To: Will Deacon Cc: catalin.marinas@arm.com, anshuman.khandual@arm.com, quic_zhenhuah@quicinc.com, ryan.roberts@arm.com, kevin.brodsky@arm.com, yangyicong@hisilicon.com, joey.gouly@arm.com, linux-arm-kernel@lists.infradead.org, linux-kernel@vger.kernel.org, david@redhat.com, mark.rutland@arm.com, urezki@gmail.com, jthoughton@google.com References: <20250723161827.15802-1-dev.jain@arm.com> <839ac455-f954-428f-b1a7-89778c57ee8b@arm.com> Content-Language: en-US From: Dev Jain In-Reply-To: Content-Type: text/plain; charset=UTF-8; format=flowed Content-Transfer-Encoding: 7bit On 19/09/25 4:29 pm, Will Deacon wrote: > On Fri, Sep 19, 2025 at 03:58:46PM +0530, Dev Jain wrote: >> On 17/09/25 9:13 pm, Will Deacon wrote: >>> On Tue, Sep 16, 2025 at 11:30:26AM +0100, Will Deacon wrote: >>>> I'm currently trying to put together a litmus test with James (cc'd) so >>>> maybe we can help you out with that part. >>> Here's what we came up with. There's not a good way to express the IPI >>> from kick_all_cpus_sync() but it turns out that the ISB from the TLB >>> invalidation is sufficient anyway. Does it make sense to you? >>> >>> >>> AArch64 ptdump >>> Variant=Ifetch >>> { >>> uint64_t pud=0xa110c; >>> uint64_t pmd; >>> >>> 0:X0=label:"P1:L0"; 0:X1=instr:"NOP"; 0:X2=lock; 0:X3=pud; 0:X4=pmd; >>> 1:X1=0xdead; 1:X2=lock; 1:X3=pud; 1:X4=pmd; >>> } >>> P0 | P1 ; >>> (* static_key_enable *) | (* pud_free_pmd_page *) ; >>> STR W1, [X0] | LDR X9, [X3] ; >>> DC CVAU,X0 | STR XZR, [X3] ; >>> DSB ISH | DSB ISH ; >>> IC IVAU,X0 | ISB ; >>> DSB ISH | ; >>> ISB | (* static key *) ; >>> | L0: ; >>> (* mmap_lock *) | B out1 ; >>> Lwlock: | ; >>> MOV W7, #1 | (* mmap_lock *) ; >>> SWPA W7, W8, [X2] | Lrlock: ; >>> | MOV W7, #1 ; >>> | SWPA W7, W8, [X2] ; >>> (* walk pgtable *) | ; >>> LDR X9, [X3] | (* mmap_unlock *) ; >>> CBZ X9, out0 | STLR WZR, [X2] ; >>> EOR X10, X9, X9 | ; >>> LDR X11, [X4, X10] | out1: ; >>> | EOR X10, X9, X9 ; >>> out0: | STR X1, [X4, X10] ; >>> >>> exists (0:X8=0 /\ 1:X8=0 /\ (* Lock acquisitions succeed *) >>> 0:X9=0xa110c /\ (* P0 sees the valid PUD ...*) >>> 0:X11=0xdead) (* ... but the freed PMD *) >>> >>> >>> Will >> Is the syntax correct? I cannot use the herd7 command to run this. > Weird, what happens? It runs for me: > > $ herd7 -version > 7.58+1, Rev: e39a86f5d59dee3174d08d9ab5b13155c75936fd > > $ herd7 ptdump.litmus > Test ptdump Allowed > States 5 > 0:X8=0; 0:X9=0; 0:X11=0; 1:X8=0; > 0:X8=0; 0:X9=0; 0:X11=0; 1:X8=1; > 0:X8=0; 0:X9=659724; 0:X11=0; 1:X8=1; > 0:X8=0; 0:X9=659724; 0:X11=57005; 1:X8=1; > 0:X8=1; 0:X9=0; 0:X11=0; 1:X8=0; > No > Witnesses > Positive: 0 Negative: 9 > Flag Assuming-common-inner-shareable-domain > Condition exists (0:X8=0 /\ 1:X8=0 /\ 0:X9=659724 /\ 0:X11=57005) > Observation ptdump Never 0 9 > Time ptdump 1.65 > Hash=238908ee9413a36507c61b92a31a366a I was using some other command :) yup this works. I'll try posting the next version today itself, but will you be okay merging this if I post on Monday? > > Will