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 X-Spam-Level: X-Spam-Status: No, score=-28.3 required=3.0 tests=BAYES_00,DKIM_SIGNED, DKIM_VALID,DKIM_VALID_AU,HEADER_FROM_DIFFERENT_DOMAINS,INCLUDES_CR_TRAILER, INCLUDES_PATCH,MAILING_LIST_MULTI,MENTIONS_GIT_HOSTING,SPF_HELO_NONE,SPF_PASS, USER_IN_DEF_DKIM_WL autolearn=ham autolearn_force=no version=3.4.0 Received: from mail.kernel.org (mail.kernel.org [198.145.29.99]) by smtp.lore.kernel.org (Postfix) with ESMTP id 56B6AC433ED for ; Thu, 6 May 2021 07:29:47 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id 0F49C61176 for ; Thu, 6 May 2021 07:29:47 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S233394AbhEFHan (ORCPT ); Thu, 6 May 2021 03:30:43 -0400 Received: from linux.microsoft.com ([13.77.154.182]:33886 "EHLO linux.microsoft.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S232271AbhEFHam (ORCPT ); Thu, 6 May 2021 03:30:42 -0400 Received: from minint-m3g9p8n.europe.corp.microsoft.com (unknown [49.207.195.141]) by linux.microsoft.com (Postfix) with ESMTPSA id C4D3120B7178; Thu, 6 May 2021 00:29:42 -0700 (PDT) DKIM-Filter: OpenDKIM Filter v2.11.0 linux.microsoft.com C4D3120B7178 DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=linux.microsoft.com; s=default; t=1620286184; bh=+D2bXIhtPis6G949XVk0e9GC9p12MK88hwh6XdzmYHA=; h=Subject:From:In-Reply-To:Date:Cc:References:To:From; b=q6U1sjxoBgBWc46EWZ/JyYKyMBKfB0uBFyvpg9eOq0yHv9q+t/vawmJqgcBxI6Cpw ezLytgctJuDUfUtSHVydpMc5et4vMI3mOkHw7yFHNSFI5iiNxWRXvrIGQfd9fkRqTq Y+cBQn4vXhxPRnxW/A8PmJnkzs+9+30bUelzwoH4= Content-Type: text/plain; charset=utf-8 Mime-Version: 1.0 (Mac OS X Mail 14.0 \(3654.60.0.2.21\)) Subject: Re: [PATCH v2 1/2] optee: fix tee out of memory failure seen during kexec reboot From: Allen Pais In-Reply-To: Date: Thu, 6 May 2021 12:59:40 +0530 Cc: Allen Pais , zajec5@gmail.com, bcm-kernel-feedback-list@broadcom.com, Linux ARM , Linux Kernel Mailing List , OP-TEE TrustedFirmware Content-Transfer-Encoding: quoted-printable Message-Id: References: <20210225090610.242623-1-allen.lkml@gmail.com> <20210225090610.242623-2-allen.lkml@gmail.com> <9a6c017c-d156-f939-f907-d6dfe83c41ac@linux.microsoft.com> <409F60D9-F0FB-4B69-B64B-CC6B3704038E@linux.microsoft.com> <51FC863B-96C5-47BA-8EBF-3D9FB6DE7DD2@linux.microsoft.com> To: Jens Wiklander X-Mailer: Apple Mail (2.3654.60.0.2.21) Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org >>=20 >>>>>>>> [ 0.368428] tee_bnxt_fw optee-clnt0: tee_shm_alloc failed >>>>>>>> [ 0.368461] tee_bnxt_fw: probe of optee-clnt0 failed with = error -22 >>>>>>>>=20 >>>>>>>> tee_shm_release() is not invoked on dma shm buffer. >>>>>>>>=20 >>>>>>>> Implement .shutdown() method to handle the release of the = buffers >>>>>>>> correctly. >>>>>>>>=20 >>>>>>>> More info: >>>>>>>> https://github.com/OP-TEE/optee_os/issues/3637 >>>>>>>>=20 >>>>>>>> Signed-off-by: Allen Pais >>>>>>>> --- >>>>>>>> drivers/tee/optee/core.c | 20 ++++++++++++++++++++ >>>>>>>> 1 file changed, 20 insertions(+) >>>>>>>=20 >>>>>>> This looks good to me. Do you have a practical way of testing = this on >>>>>>> QEMU for instance? >>>>>>>=20 >>>>>>=20 >>>>>> Jens, >>>>>>=20 >>>>>> I could not reproduce nor create a setup using QEMU, I could only >>>>>> do it on a real h/w. >>>>>>=20 >>>>>> I have extensively tested the fix and I don't see any issues. >>>>>=20 >>>>> I did a few test runs too, seems OK. >>>>=20 >>>> I carried these changes and have not run into any issues with Kexec = so far. >>>> Last week, while trying out kdump, we ran into a crash(this is when = the >>>> Kdump kernel reboots). >>>>=20 >>>> $echo c > /proc/sysrq-trigger >>>>=20 >>>> Leads to: >>>>=20 >>>> [ 18.004831] Unable to handle kernel paging request at virtual = address ffff0008dcef6758 >>>> [ 18.013002] Mem abort info: >>>> [ 18.015885] ESR =3D 0x96000005 >>>> [ 18.019034] EC =3D 0x25: DABT (current EL), IL =3D 32 bits >>>> [ 18.024516] SET =3D 0, FnV =3D 0 >>>> [ 18.027667] EA =3D 0, S1PTW =3D 0 >>>> [ 18.030905] Data abort info: >>>> [ 18.033877] ISV =3D 0, ISS =3D 0x00000005 >>>> [ 18.037835] CM =3D 0, WnR =3D 0 >>>> [ 18.040896] swapper pgtable: 4k pages, 48-bit VAs, = pgdp=3D0000000970a78000 >>>> [ 18.047811] [ffff0008dcef6758] pgd=3D000000097fbf9003, = pud=3D0000000000000000 >>>> [ 18.054819] Internal error: Oops: 96000005 [#1] SMP >>>> [ 18.059850] Modules linked in: bnxt_en pcie_iproc_platform = pcie_iproc diagbe(O) >>>> [ 18.067395] CPU: 3 PID: 1 Comm: systemd-shutdow Tainted: G = O 5.4.83-microsoft-standard #1 >>>> [ 18.077174] Hardware name: Overlake (DT) >>>> [ 18.081219] pstate: 80400005 (Nzcv daif +PAN -UAO) >>>> [ 18.086170] pc : tee_shm_free+0x18/0x48 >>>> [ 18.090126] lr : optee_disable_shm_cache+0xa4/0xf0 >>>> [ 18.095066] sp : ffff80001005bb90 >>>> [ 18.098484] x29: ffff80001005bb90 x28: ffff000037e20000 >>>> [ 18.103962] x27: 0000000000000000 x26: ffff00003ed10490 >>>> [ 18.109440] x25: ffffca760e975f90 x24: 0000000000000000 >>>> [ 18.114918] x23: ffffca760ed79808 x22: ffff00003ec66e18 >>>> [ 18.120396] x21: ffff80001005bc08 x20: 00000000b200000a >>>> [ 18.125874] x19: ffff0008dcef6700 x18: 0000000000000010 >>>> [ 18.131352] x17: 0000000000000000 x16: 0000000000000000 >>>> [ 18.136829] x15: ffffffffffffffff x14: ffffca760ed79808 >>>> [ 18.142307] x13: ffff80009005b897 x12: ffff80001005b89f >>>> [ 18.147786] x11: ffffca760eda4000 x10: ffff80001005b820 >>>> [ 18.153264] x9 : 00000000ffffffd0 x8 : ffffca760e59b2c0 >>>> [ 18.158742] x7 : 0000000000000000 x6 : 0000000000000000 >>>> [ 18.164220] x5 : 0000000000000000 x4 : 0000000000000000 >>>> [ 18.169698] x3 : 0000000000000000 x2 : ffff0008dcef6700 >>>> [ 18.175175] x1 : 00000000ffff0008 x0 : ffffca760e59ca04 >>>> [ 18.180654] Call trace: >>>> [ 18.183176] tee_shm_free+0x18/0x48 >>>> [ 18.186773] optee_disable_shm_cache+0xa4/0xf0 >>>> [ 18.191356] optee_shutdown+0x20/0x30 >>>> [ 18.195135] platform_drv_shutdown+0x2c/0x38 >>>> [ 18.199538] device_shutdown+0x180/0x298 >>>> [ 18.203586] kernel_restart_prepare+0x44/0x50 >>>> [ 18.208078] kernel_restart+0x20/0x68 >>>> [ 18.211853] __do_sys_reboot+0x104/0x258 >>>> [ 18.215899] __arm64_sys_reboot+0x2c/0x38 >>>> [ 18.220035] el0_svc_handler+0x90/0x138 >>>> [ 18.223991] el0_svc+0x8/0x208 >>>> [ 18.227143] Code: f9000bf3 aa0003f3 aa1e03e0 d503201f (b9405a60) >>>> [ 18.233435] ---[ end trace 835d756cd66aa959 ]--- >>>> [ 18.238621] Kernel panic - not syncing: Fatal exception >>>> [ 18.244014] Kernel Offset: 0x4a75fde00000 from = 0xffff800010000000 >>>> [ 18.250299] PHYS_OFFSET: 0xffff99c680000000 >>>> [ 18.254613] CPU features: 0x0002,21806008 >>>> [ 18.258747] Memory Limit: none >>>> [ 18.262310] ---[ end Kernel panic - not syncing: Fatal exception = ]=E2=80=94 >>>>=20 >>>> I see that before secure world returns = OPTEE_SMC_RETURN_ENOTAVAIL(which >>>> Should disable and clear all the cache) we run into the crash = trying to free shm. >>>>=20 >>>> Thoughts? >>>=20 >>> It seems that the pointer is invalid, but the pointer doesn't look >>> like garbage. Could the kernel have unmapped the memory area = covering >>> that address? >>>=20 >>=20 >> Yes, I am not entirely sure if the kernel had the time to unmap the = memory. >> Right after triggering the crash the kdump kernel is booted and I see = the following >>=20 >> [ 2.050145] optee: probing for conduit method. >> [ 2.054743] optee: revision 3.6 (f84427aa) >> [ 2.054821] optee: dynamic shared memory is enabled >> [ 2.066186] optee: initialized driver >>=20 >> Could this be previous un-released maps causing corruption? >=20 > Aha, yes, that could be it. >=20 How about checking for the ptr? diff --git a/drivers/tee/optee/call.c b/drivers/tee/optee/call.c index aadedec3bfe7..8dc4fe9a1588 100644 --- a/drivers/tee/optee/call.c +++ b/drivers/tee/optee/call.c @@ -426,10 +426,12 @@ void optee_disable_shm_cache(struct optee *optee) if (res.result.status =3D=3D OPTEE_SMC_RETURN_ENOTAVAIL) break; /* All shm's freed */ if (res.result.status =3D=3D OPTEE_SMC_RETURN_OK) { - struct tee_shm *shm; + struct tee_shm *shm =3D NULL; =20 shm =3D reg_pair_to_ptr(res.result.shm_upper32, res.result.shm_lower32); + if (IS_ERR(shm)) + return PTR_ERR(shm); tee_shm_free(shm); Thanks.=