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 vger.kernel.org (vger.kernel.org [23.128.96.18]) by smtp.lore.kernel.org (Postfix) with ESMTP id 47D7CC433F5 for ; Fri, 30 Sep 2022 12:11:34 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S231510AbiI3MLc (ORCPT ); Fri, 30 Sep 2022 08:11:32 -0400 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:55538 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S231669AbiI3MLO (ORCPT ); Fri, 30 Sep 2022 08:11:14 -0400 Received: from foss.arm.com (foss.arm.com [217.140.110.172]) by lindbergh.monkeyblade.net (Postfix) with ESMTP id 08CFAB5159; Fri, 30 Sep 2022 05:10:51 -0700 (PDT) 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 3A8FA1474; Fri, 30 Sep 2022 05:10:57 -0700 (PDT) Received: from [10.57.65.170] (unknown [10.57.65.170]) by usa-sjc-imap-foss1.foss.arm.com (Postfix) with ESMTPSA id 9328B3F73B; Fri, 30 Sep 2022 05:10:48 -0700 (PDT) Message-ID: <461a5187-fc7a-b7f6-84da-0e947f764a0a@arm.com> Date: Fri, 30 Sep 2022 13:10:28 +0100 MIME-Version: 1.0 User-Agent: Mozilla/5.0 (Windows NT 10.0; rv:102.0) Gecko/20100101 Thunderbird/102.3.0 Subject: Re: [PATCH v2 2/4] spi: Fix cache corruption due to DMA/PIO overlap Content-Language: en-GB To: Marek Szyprowski , Vincent Whitchurch , broonie@kernel.org, krzysztof.kozlowski@linaro.org, andi@etezian.org, Christoph Hellwig Cc: kernel@axis.com, alim.akhtar@samsung.com, linux-spi@vger.kernel.org, linux-kernel@vger.kernel.org, linux-samsung-soc@vger.kernel.org, linux-arm-kernel@lists.infradead.org, "iommu@lists.linux-foundation.org" References: <20220927112117.77599-1-vincent.whitchurch@axis.com> <20220927112117.77599-3-vincent.whitchurch@axis.com> From: Robin Murphy In-Reply-To: Content-Type: text/plain; charset=UTF-8; format=flowed Content-Transfer-Encoding: 8bit Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org On 2022-09-30 12:20, Marek Szyprowski wrote: > Hi, > > CCed: Christoph and Robin, as the issue is partially dma-mapping related. > > On 27.09.2022 13:21, Vincent Whitchurch wrote: >> The SPI core DMA mapping support performs cache management once for the >> entire message and not between transfers, and this leads to cache >> corruption if a message has two or more RX transfers with both >> transfers targeting the same cache line, and the controller driver >> decides to handle one using DMA and the other using PIO (for example, >> because one is much larger than the other). >> >> Fix it by syncing before/after the actual transfers. This also means >> that we can skip the sync during the map/unmap of the message. >> >> Fixes: 99adef310f68 ("spi: Provide core support for DMA mapping transfers") >> Signed-off-by: Vincent Whitchurch >> --- > > This patch landed in linux next-20220929 as commit 0c17ba73c08f ("spi: > Fix cache corruption due to DMA/PIO overlap"). Unfortunately it causes > kernel oops on one of my test systems: > > 8<--- cut here --- > Unable to handle kernel NULL pointer dereference at virtual address 0000000c > [0000000c] *pgd=00000000 > Internal error: Oops: 5 [#1] PREEMPT SMP ARM > Modules linked in: cmac bnep btsdio hci_uart btbcm s5p_mfc btintel > brcmfmac bluetooth videobuf2_dma_contig videobuf2_memops videobuf2_v4l2 > videobuf2_common videodev cfg80211 mc ecdh_generic ecc brcmutil > CPU: 0 PID: 12 Comm: kworker/0:1 Not tainted > 6.0.0-rc7-next-20220929-dirty #12903 > Hardware name: Samsung Exynos (Flattened Device Tree) > Workqueue: events ax88796c_work > PC is at dma_direct_sync_sg_for_device+0x24/0xb8 > LR is at spi_transfer_one_message+0x4c4/0xabc > pc : []    lr : []    psr: 20000013 > ... > Process kworker/0:1 (pid: 12, stack limit = 0xca429928) > Stack: (0xe0071d38 to 0xe0072000) > ... >  dma_direct_sync_sg_for_device from spi_transfer_one_message+0x4c4/0xabc >  spi_transfer_one_message from __spi_pump_transfer_message+0x300/0x770 >  __spi_pump_transfer_message from __spi_sync+0x304/0x3f4 >  __spi_sync from spi_sync+0x28/0x40 >  spi_sync from axspi_read_rxq+0x98/0xc8 >  axspi_read_rxq from ax88796c_work+0x7a8/0xf6c >  ax88796c_work from process_one_work+0x288/0x774 >  process_one_work from worker_thread+0x44/0x504 >  worker_thread from kthread+0xf0/0x124 >  kthread from ret_from_fork+0x14/0x2c > Exception stack(0xe0071fb0 to 0xe0071ff8) > ... > ---[ end trace 0000000000000000 ]--- > > This happens because sg_free_table() doesn't clear table->orig_nents nor > table->nents. If the given spi xfer object is reused without dma-mapped > buffer, then a NULL pointer de-reference happens at table->sgl > spi_dma_sync_for_device()/spi_dma_sync_for_cpu(). A possible fix would > be to zero table->orig_nents in spi_unmap_buf_attrs(). I will send a > patch for this soon. > > However, I think that clearing table->orig_nents and table->nents should > be added to __sg_free_table() in lib/scatterlist.c to avoid this kind of > issue in the future. This however will be a significant change that > might break code somewhere, if it relies on the nents/orig_nents value > after calling sg_free_table(). Christoph, Robin - what is your opinion? Yes, that makes sense to me: the table->nents etc. fields logically describe the list that table->sgl points to, so when it sets that to NULL it seems right to also update the corresponding fields accordingly. I don't see much good reason for code to poking into an sg_table after it's been freed, other that to reinitialise it with sg_alloc_table() which would overwrite those fields anyway, so I can't imagine it's a particularly risky change. That said, maybe this is something that's better to catch than to paper over? Arguably the real bug here is that spi_unmap_buf() and the new sync functions should use the same "{tx,rx}_buf != NULL" condition that spi_map_buf() used for the DMA mapping decision in the first place. Thanks, Robin. > > >> drivers/spi/spi.c | 109 +++++++++++++++++++++++++++++++++++++--------- >> 1 file changed, 88 insertions(+), 21 deletions(-) >> >> ... > > Best regards 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 bombadil.infradead.org (bombadil.infradead.org [198.137.202.133]) (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 9DB7EC433FE for ; Fri, 30 Sep 2022 12:11:59 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; q=dns/txt; c=relaxed/relaxed; d=lists.infradead.org; s=bombadil.20210309; h=Sender:Content-Type: Content-Transfer-Encoding:List-Subscribe:List-Help:List-Post:List-Archive: List-Unsubscribe:List-Id:In-Reply-To:From:References:Cc:To:Subject: MIME-Version:Date:Message-ID:Reply-To:Content-ID:Content-Description: Resent-Date:Resent-From:Resent-Sender:Resent-To:Resent-Cc:Resent-Message-ID: List-Owner; bh=y0fQi672xT2n1rTWQou8CTjkqcEznYx7Jv+6EOGk61o=; b=P//gf2zpuHE+Th dvQ6lED5lbBezeHkwNm/t8/q/O9NumxxAZo33OTnBSFmcFB5w1yTBb/OC7a5sycAv5fuiBrq8n5WI /rVIy+iC1WVT2T0rxsOuaI7whNAZfi1lpk7pZohyWYNkrDSAS3X6YjK48k5QoFBxGMkczRlusxxaB srRnPNWJKDvgdgTw48Vgvxox8pqRHmIQpwzEbpKIX74kp9gkT90xGNVdVcCsC+OrSJhO8wNIgq/Rs j/c8QRtnrzkaDVrcznK2CD1bbrb8U/GgWuwWTdMMVEU1NC2xVcJEC4jPCTwo3zE+cyfhFvd0BWFTJ TvJVX6pSPgZZm2aq/Y6w==; Received: from localhost ([::1] helo=bombadil.infradead.org) by bombadil.infradead.org with esmtp (Exim 4.94.2 #2 (Red Hat Linux)) id 1oeEr3-0092os-Qc; Fri, 30 Sep 2022 12:10:57 +0000 Received: from foss.arm.com ([217.140.110.172]) by bombadil.infradead.org with esmtp (Exim 4.94.2 #2 (Red Hat Linux)) id 1oeEqz-0092mI-Vc for linux-arm-kernel@lists.infradead.org; Fri, 30 Sep 2022 12:10:56 +0000 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 3A8FA1474; Fri, 30 Sep 2022 05:10:57 -0700 (PDT) Received: from [10.57.65.170] (unknown [10.57.65.170]) by usa-sjc-imap-foss1.foss.arm.com (Postfix) with ESMTPSA id 9328B3F73B; Fri, 30 Sep 2022 05:10:48 -0700 (PDT) Message-ID: <461a5187-fc7a-b7f6-84da-0e947f764a0a@arm.com> Date: Fri, 30 Sep 2022 13:10:28 +0100 MIME-Version: 1.0 User-Agent: Mozilla/5.0 (Windows NT 10.0; rv:102.0) Gecko/20100101 Thunderbird/102.3.0 Subject: Re: [PATCH v2 2/4] spi: Fix cache corruption due to DMA/PIO overlap Content-Language: en-GB To: Marek Szyprowski , Vincent Whitchurch , broonie@kernel.org, krzysztof.kozlowski@linaro.org, andi@etezian.org, Christoph Hellwig Cc: kernel@axis.com, alim.akhtar@samsung.com, linux-spi@vger.kernel.org, linux-kernel@vger.kernel.org, linux-samsung-soc@vger.kernel.org, linux-arm-kernel@lists.infradead.org, "iommu@lists.linux-foundation.org" References: <20220927112117.77599-1-vincent.whitchurch@axis.com> <20220927112117.77599-3-vincent.whitchurch@axis.com> From: Robin Murphy In-Reply-To: X-CRM114-Version: 20100106-BlameMichelson ( TRE 0.8.0 (BSD) ) MR-646709E3 X-CRM114-CacheID: sfid-20220930_051054_136762_D6997D55 X-CRM114-Status: GOOD ( 27.46 ) X-BeenThere: linux-arm-kernel@lists.infradead.org X-Mailman-Version: 2.1.34 Precedence: list List-Id: List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Content-Transfer-Encoding: base64 Content-Type: text/plain; charset="utf-8"; Format="flowed" Sender: "linux-arm-kernel" Errors-To: linux-arm-kernel-bounces+linux-arm-kernel=archiver.kernel.org@lists.infradead.org T24gMjAyMi0wOS0zMCAxMjoyMCwgTWFyZWsgU3p5cHJvd3NraSB3cm90ZToKPiBIaSwKPiAKPiBD Q2VkOiBDaHJpc3RvcGggYW5kIFJvYmluLCBhcyB0aGUgaXNzdWUgaXMgcGFydGlhbGx5IGRtYS1t YXBwaW5nIHJlbGF0ZWQuCj4gCj4gT24gMjcuMDkuMjAyMiAxMzoyMSwgVmluY2VudCBXaGl0Y2h1 cmNoIHdyb3RlOgo+PiBUaGUgU1BJIGNvcmUgRE1BIG1hcHBpbmcgc3VwcG9ydCBwZXJmb3JtcyBj YWNoZSBtYW5hZ2VtZW50IG9uY2UgZm9yIHRoZQo+PiBlbnRpcmUgbWVzc2FnZSBhbmQgbm90IGJl dHdlZW4gdHJhbnNmZXJzLCBhbmQgdGhpcyBsZWFkcyB0byBjYWNoZQo+PiBjb3JydXB0aW9uIGlm IGEgbWVzc2FnZSBoYXMgdHdvIG9yIG1vcmUgUlggdHJhbnNmZXJzIHdpdGggYm90aAo+PiB0cmFu c2ZlcnMgdGFyZ2V0aW5nIHRoZSBzYW1lIGNhY2hlIGxpbmUsIGFuZCB0aGUgY29udHJvbGxlciBk cml2ZXIKPj4gZGVjaWRlcyB0byBoYW5kbGUgb25lIHVzaW5nIERNQSBhbmQgdGhlIG90aGVyIHVz aW5nIFBJTyAoZm9yIGV4YW1wbGUsCj4+IGJlY2F1c2Ugb25lIGlzIG11Y2ggbGFyZ2VyIHRoYW4g dGhlIG90aGVyKS4KPj4KPj4gRml4IGl0IGJ5IHN5bmNpbmcgYmVmb3JlL2FmdGVyIHRoZSBhY3R1 YWwgdHJhbnNmZXJzLiAgVGhpcyBhbHNvIG1lYW5zCj4+IHRoYXQgd2UgY2FuIHNraXAgdGhlIHN5 bmMgZHVyaW5nIHRoZSBtYXAvdW5tYXAgb2YgdGhlIG1lc3NhZ2UuCj4+Cj4+IEZpeGVzOiA5OWFk ZWYzMTBmNjggKCJzcGk6IFByb3ZpZGUgY29yZSBzdXBwb3J0IGZvciBETUEgbWFwcGluZyB0cmFu c2ZlcnMiKQo+PiBTaWduZWQtb2ZmLWJ5OiBWaW5jZW50IFdoaXRjaHVyY2ggPHZpbmNlbnQud2hp dGNodXJjaEBheGlzLmNvbT4KPj4gLS0tCj4gCj4gVGhpcyBwYXRjaCBsYW5kZWQgaW4gbGludXgg bmV4dC0yMDIyMDkyOSBhcyBjb21taXQgMGMxN2JhNzNjMDhmICgic3BpOgo+IEZpeCBjYWNoZSBj b3JydXB0aW9uIGR1ZSB0byBETUEvUElPIG92ZXJsYXAiKS4gVW5mb3J0dW5hdGVseSBpdCBjYXVz ZXMKPiBrZXJuZWwgb29wcyBvbiBvbmUgb2YgbXkgdGVzdCBzeXN0ZW1zOgo+IAo+IDg8LS0tIGN1 dCBoZXJlIC0tLQo+IFVuYWJsZSB0byBoYW5kbGUga2VybmVsIE5VTEwgcG9pbnRlciBkZXJlZmVy ZW5jZSBhdCB2aXJ0dWFsIGFkZHJlc3MgMDAwMDAwMGMKPiBbMDAwMDAwMGNdICpwZ2Q9MDAwMDAw MDAKPiBJbnRlcm5hbCBlcnJvcjogT29wczogNSBbIzFdIFBSRUVNUFQgU01QIEFSTQo+IE1vZHVs ZXMgbGlua2VkIGluOiBjbWFjIGJuZXAgYnRzZGlvIGhjaV91YXJ0IGJ0YmNtIHM1cF9tZmMgYnRp bnRlbAo+IGJyY21mbWFjIGJsdWV0b290aCB2aWRlb2J1ZjJfZG1hX2NvbnRpZyB2aWRlb2J1ZjJf bWVtb3BzIHZpZGVvYnVmMl92NGwyCj4gdmlkZW9idWYyX2NvbW1vbiB2aWRlb2RldiBjZmc4MDIx MSBtYyBlY2RoX2dlbmVyaWMgZWNjIGJyY211dGlsCj4gQ1BVOiAwIFBJRDogMTIgQ29tbToga3dv cmtlci8wOjEgTm90IHRhaW50ZWQKPiA2LjAuMC1yYzctbmV4dC0yMDIyMDkyOS1kaXJ0eSAjMTI5 MDMKPiBIYXJkd2FyZSBuYW1lOiBTYW1zdW5nIEV4eW5vcyAoRmxhdHRlbmVkIERldmljZSBUcmVl KQo+IFdvcmtxdWV1ZTogZXZlbnRzIGF4ODg3OTZjX3dvcmsKPiBQQyBpcyBhdCBkbWFfZGlyZWN0 X3N5bmNfc2dfZm9yX2RldmljZSsweDI0LzB4YjgKPiBMUiBpcyBhdCBzcGlfdHJhbnNmZXJfb25l X21lc3NhZ2UrMHg0YzQvMHhhYmMKPiBwYyA6IFs8YzAxY2JjZjA+XcKgwqDCoCBsciA6IFs8YzA3 MzlmY2M+XcKgwqDCoCBwc3I6IDIwMDAwMDEzCj4gLi4uCj4gUHJvY2VzcyBrd29ya2VyLzA6MSAo cGlkOiAxMiwgc3RhY2sgbGltaXQgPSAweGNhNDI5OTI4KQo+IFN0YWNrOiAoMHhlMDA3MWQzOCB0 byAweGUwMDcyMDAwKQo+IC4uLgo+ICAgwqBkbWFfZGlyZWN0X3N5bmNfc2dfZm9yX2RldmljZSBm cm9tIHNwaV90cmFuc2Zlcl9vbmVfbWVzc2FnZSsweDRjNC8weGFiYwo+ICAgwqBzcGlfdHJhbnNm ZXJfb25lX21lc3NhZ2UgZnJvbSBfX3NwaV9wdW1wX3RyYW5zZmVyX21lc3NhZ2UrMHgzMDAvMHg3 NzAKPiAgIMKgX19zcGlfcHVtcF90cmFuc2Zlcl9tZXNzYWdlIGZyb20gX19zcGlfc3luYysweDMw NC8weDNmNAo+ICAgwqBfX3NwaV9zeW5jIGZyb20gc3BpX3N5bmMrMHgyOC8weDQwCj4gICDCoHNw aV9zeW5jIGZyb20gYXhzcGlfcmVhZF9yeHErMHg5OC8weGM4Cj4gICDCoGF4c3BpX3JlYWRfcnhx IGZyb20gYXg4ODc5NmNfd29yaysweDdhOC8weGY2Ywo+ICAgwqBheDg4Nzk2Y193b3JrIGZyb20g cHJvY2Vzc19vbmVfd29yaysweDI4OC8weDc3NAo+ICAgwqBwcm9jZXNzX29uZV93b3JrIGZyb20g d29ya2VyX3RocmVhZCsweDQ0LzB4NTA0Cj4gICDCoHdvcmtlcl90aHJlYWQgZnJvbSBrdGhyZWFk KzB4ZjAvMHgxMjQKPiAgIMKga3RocmVhZCBmcm9tIHJldF9mcm9tX2ZvcmsrMHgxNC8weDJjCj4g RXhjZXB0aW9uIHN0YWNrKDB4ZTAwNzFmYjAgdG8gMHhlMDA3MWZmOCkKPiAuLi4KPiAtLS1bIGVu ZCB0cmFjZSAwMDAwMDAwMDAwMDAwMDAwIF0tLS0KPiAKPiBUaGlzIGhhcHBlbnMgYmVjYXVzZSBz Z19mcmVlX3RhYmxlKCkgZG9lc24ndCBjbGVhciB0YWJsZS0+b3JpZ19uZW50cyBub3IKPiB0YWJs ZS0+bmVudHMuIElmIHRoZSBnaXZlbiBzcGkgeGZlciBvYmplY3QgaXMgcmV1c2VkIHdpdGhvdXQg ZG1hLW1hcHBlZAo+IGJ1ZmZlciwgdGhlbiBhIE5VTEwgcG9pbnRlciBkZS1yZWZlcmVuY2UgaGFw cGVucyBhdCB0YWJsZS0+c2dsCj4gc3BpX2RtYV9zeW5jX2Zvcl9kZXZpY2UoKS9zcGlfZG1hX3N5 bmNfZm9yX2NwdSgpLiBBIHBvc3NpYmxlIGZpeCB3b3VsZAo+IGJlIHRvIHplcm8gdGFibGUtPm9y aWdfbmVudHMgaW4gc3BpX3VubWFwX2J1Zl9hdHRycygpLiBJIHdpbGwgc2VuZCBhCj4gcGF0Y2gg Zm9yIHRoaXMgc29vbi4KPiAKPiBIb3dldmVyLCBJIHRoaW5rIHRoYXQgY2xlYXJpbmcgdGFibGUt Pm9yaWdfbmVudHMgYW5kIHRhYmxlLT5uZW50cyBzaG91bGQKPiBiZSBhZGRlZCB0byBfX3NnX2Zy ZWVfdGFibGUoKSBpbiBsaWIvc2NhdHRlcmxpc3QuYyB0byBhdm9pZCB0aGlzIGtpbmQgb2YKPiBp c3N1ZSBpbiB0aGUgZnV0dXJlLiBUaGlzIGhvd2V2ZXIgd2lsbCBiZSBhIHNpZ25pZmljYW50IGNo YW5nZSB0aGF0Cj4gbWlnaHQgYnJlYWsgY29kZSBzb21ld2hlcmUsIGlmIGl0IHJlbGllcyBvbiB0 aGUgbmVudHMvb3JpZ19uZW50cyB2YWx1ZQo+IGFmdGVyIGNhbGxpbmcgc2dfZnJlZV90YWJsZSgp LiBDaHJpc3RvcGgsIFJvYmluIC0gd2hhdCBpcyB5b3VyIG9waW5pb24/CgpZZXMsIHRoYXQgbWFr ZXMgc2Vuc2UgdG8gbWU6IHRoZSB0YWJsZS0+bmVudHMgZXRjLiBmaWVsZHMgbG9naWNhbGx5IApk ZXNjcmliZSB0aGUgbGlzdCB0aGF0IHRhYmxlLT5zZ2wgcG9pbnRzIHRvLCBzbyB3aGVuIGl0IHNl dHMgdGhhdCB0byAKTlVMTCBpdCBzZWVtcyByaWdodCB0byBhbHNvIHVwZGF0ZSB0aGUgY29ycmVz cG9uZGluZyBmaWVsZHMgYWNjb3JkaW5nbHkuIApJIGRvbid0IHNlZSBtdWNoIGdvb2QgcmVhc29u IGZvciBjb2RlIHRvIHBva2luZyBpbnRvIGFuIHNnX3RhYmxlIGFmdGVyIAppdCdzIGJlZW4gZnJl ZWQsIG90aGVyIHRoYXQgdG8gcmVpbml0aWFsaXNlIGl0IHdpdGggc2dfYWxsb2NfdGFibGUoKSAK d2hpY2ggd291bGQgb3ZlcndyaXRlIHRob3NlIGZpZWxkcyBhbnl3YXksIHNvIEkgY2FuJ3QgaW1h Z2luZSBpdCdzIGEgCnBhcnRpY3VsYXJseSByaXNreSBjaGFuZ2UuCgpUaGF0IHNhaWQsIG1heWJl IHRoaXMgaXMgc29tZXRoaW5nIHRoYXQncyBiZXR0ZXIgdG8gY2F0Y2ggdGhhbiB0byBwYXBlciAK b3Zlcj8gQXJndWFibHkgdGhlIHJlYWwgYnVnIGhlcmUgaXMgdGhhdCBzcGlfdW5tYXBfYnVmKCkg YW5kIHRoZSBuZXcgCnN5bmMgZnVuY3Rpb25zIHNob3VsZCB1c2UgdGhlIHNhbWUgInt0eCxyeH1f YnVmICE9IE5VTEwiIGNvbmRpdGlvbiB0aGF0IApzcGlfbWFwX2J1ZigpIHVzZWQgZm9yIHRoZSBE TUEgbWFwcGluZyBkZWNpc2lvbiBpbiB0aGUgZmlyc3QgcGxhY2UuCgpUaGFua3MsClJvYmluLgoK PiAKPiAKPj4gICAgZHJpdmVycy9zcGkvc3BpLmMgfCAxMDkgKysrKysrKysrKysrKysrKysrKysr KysrKysrKysrKysrKysrKy0tLS0tLS0tLQo+PiAgICAxIGZpbGUgY2hhbmdlZCwgODggaW5zZXJ0 aW9ucygrKSwgMjEgZGVsZXRpb25zKC0pCj4+Cj4+IC4uLgo+IAo+IEJlc3QgcmVnYXJkcwoKX19f X19fX19fX19fX19fX19fX19fX19fX19fX19fX19fX19fX19fX19fX19fX18KbGludXgtYXJtLWtl cm5lbCBtYWlsaW5nIGxpc3QKbGludXgtYXJtLWtlcm5lbEBsaXN0cy5pbmZyYWRlYWQub3JnCmh0 dHA6Ly9saXN0cy5pbmZyYWRlYWQub3JnL21haWxtYW4vbGlzdGluZm8vbGludXgtYXJtLWtlcm5l bAo=