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=-8.2 required=3.0 tests=HEADER_FROM_DIFFERENT_DOMAINS, INCLUDES_PATCH,MAILING_LIST_MULTI,SIGNED_OFF_BY,SPF_HELO_NONE,SPF_PASS, USER_AGENT_SANE_2 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 83EC7C5DF60 for ; Tue, 5 Nov 2019 19:03:51 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.kernel.org (Postfix) with ESMTP id 5756D217F4 for ; Tue, 5 Nov 2019 19:03:51 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S2390776AbfKETDu convert rfc822-to-8bit (ORCPT ); Tue, 5 Nov 2019 14:03:50 -0500 Received: from relay7-d.mail.gandi.net ([217.70.183.200]:48345 "EHLO relay7-d.mail.gandi.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S2390514AbfKETDu (ORCPT ); Tue, 5 Nov 2019 14:03:50 -0500 X-Originating-IP: 91.224.148.103 Received: from xps13 (unknown [91.224.148.103]) (Authenticated sender: miquel.raynal@bootlin.com) by relay7-d.mail.gandi.net (Postfix) with ESMTPSA id 4E88320004; Tue, 5 Nov 2019 19:03:46 +0000 (UTC) Date: Tue, 5 Nov 2019 20:03:44 +0100 From: Miquel Raynal To: Kamal Dasu Cc: linux-mtd@lists.infradead.org, bcm-kernel-feedback-list@broadcom.com, linux-kernel@vger.kernel.org, David Woodhouse , Brian Norris , Marek Vasut , Richard Weinberger , Vignesh Raghavendra Subject: Re: [PATCH] mtd: set mtd partition panic write flag Message-ID: <20191105200344.1e8c3eab@xps13> In-Reply-To: <20191021193343.41320-1-kdasu.kdev@gmail.com> References: <20191021193343.41320-1-kdasu.kdev@gmail.com> Organization: Bootlin X-Mailer: Claws Mail 3.17.3 (GTK+ 2.24.32; x86_64-pc-linux-gnu) MIME-Version: 1.0 Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 8BIT Sender: linux-kernel-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Hi Kamal, Richard, something to look into below :) Kamal Dasu wrote on Mon, 21 Oct 2019 15:32:52 -0400: > Check mtd panic write flag and set the mtd partition panic > write flag so that low level drivers can use it to take > required action to ensure oops data gets written to assigned > mtd partition. I feel there is something wrong with the current implementation regarding partitions but I am not sure this is the right fix. Is this something you detected with some kind of static checker or did you actually experience an issue? In the commit log you say "check mtd (I suppose you mean the master) panic write flag and set the mtd partition panic write flag" which makes sense, but in reality my understanding is that you do the opposite: you check mtd->oops_panic_write which is the partitions' structure, and set part->parent->oops_panic_write which is the master's flag. Also, I am not sure if it is worth checking anything, why not just set mtd->oops_panic_write in this function? Same comment for the -already existing- condition in mtd_panic_write. As soon as we are in these functions, we know there is a panic, right? So why checking if the bit is already set before forcing it? > > Fixes: 9f897bfdd8 ("mtd: Add flag to indicate panic_write") > Signed-off-by: Kamal Dasu > --- > drivers/mtd/mtdpart.c | 4 ++++ > 1 file changed, 4 insertions(+) > > diff --git a/drivers/mtd/mtdpart.c b/drivers/mtd/mtdpart.c > index 7328c066c5ba..b4f6479abeda 100644 > --- a/drivers/mtd/mtdpart.c > +++ b/drivers/mtd/mtdpart.c > @@ -159,6 +159,10 @@ static int part_panic_write(struct mtd_info *mtd, loff_t to, size_t len, > size_t *retlen, const u_char *buf) > { > struct mtd_part *part = mtd_to_part(mtd); > + > + if (mtd->oops_panic_write) > + part->parent->oops_panic_write = true; > + > return part->parent->_panic_write(part->parent, to + part->offset, len, > retlen, buf); > } Thanks, Miquèl 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=-8.2 required=3.0 tests=DKIMWL_WL_HIGH,DKIM_SIGNED, DKIM_VALID,HEADER_FROM_DIFFERENT_DOMAINS,INCLUDES_PATCH,MAILING_LIST_MULTI, SIGNED_OFF_BY,SPF_HELO_NONE,SPF_PASS,URIBL_BLOCKED,USER_AGENT_SANE_2 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 5574AC5DF60 for ; Tue, 5 Nov 2019 19:04:07 +0000 (UTC) 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 mail.kernel.org (Postfix) with ESMTPS id 2C6CF217F4 for ; Tue, 5 Nov 2019 19:04:07 +0000 (UTC) Authentication-Results: mail.kernel.org; dkim=pass (2048-bit key) header.d=lists.infradead.org header.i=@lists.infradead.org header.b="KdNcEcoX" DMARC-Filter: OpenDMARC Filter v1.3.2 mail.kernel.org 2C6CF217F4 Authentication-Results: mail.kernel.org; dmarc=none (p=none dis=none) header.from=bootlin.com Authentication-Results: mail.kernel.org; spf=none smtp.mailfrom=linux-mtd-bounces+linux-mtd=archiver.kernel.org@lists.infradead.org DKIM-Signature: v=1; a=rsa-sha256; q=dns/txt; c=relaxed/relaxed; d=lists.infradead.org; s=bombadil.20170209; h=Sender: Content-Transfer-Encoding:Content-Type:Cc:List-Subscribe:List-Help:List-Post: List-Archive:List-Unsubscribe:List-Id:MIME-Version:References:In-Reply-To: Message-ID:Subject:To:From:Date:Reply-To:Content-ID:Content-Description: Resent-Date:Resent-From:Resent-Sender:Resent-To:Resent-Cc:Resent-Message-ID: List-Owner; bh=mNDnUEXHiJ6/QJ5p4fSTTKRnTnLVvbMbcWEPxppHuQI=; b=KdNcEcoXGy4F6n /1XOLIwrS383Vyed02fyX06GXamlCQkLhw0j48niwcyGRKtppzhWtl/dKeZgU9F+rgJSzvnk+TFTz xuY+9JUWqLgeloszRI2o+rElMYAtMQeI/B3EgKgzWMLT5dze0ryc+sxduW86kFoJjTVbXVR/dZ4nh 5+9THCzgaNpRDP5RmN9qEyQVBtYcS3Lqqvvugq4Lch5Qdex95jCWMxfGPSIIJRABfeKnDoPBordiO UwwDWyZqP4pAE9k57e/FFzgbgFkNgWdmzo3oDxcUov3XzMpKolBJjcwgeIcMsswsUx40WQgDU2Pd8 nv+wnULnRXyD4L9rf+tA==; Received: from localhost ([127.0.0.1] helo=bombadil.infradead.org) by bombadil.infradead.org with esmtp (Exim 4.92.3 #3 (Red Hat Linux)) id 1iS47N-0002KI-H1; Tue, 05 Nov 2019 19:03:53 +0000 Received: from relay7-d.mail.gandi.net ([217.70.183.200]) by bombadil.infradead.org with esmtps (Exim 4.92.3 #3 (Red Hat Linux)) id 1iS47K-0002JA-LO for linux-mtd@lists.infradead.org; Tue, 05 Nov 2019 19:03:52 +0000 X-Originating-IP: 91.224.148.103 Received: from xps13 (unknown [91.224.148.103]) (Authenticated sender: miquel.raynal@bootlin.com) by relay7-d.mail.gandi.net (Postfix) with ESMTPSA id 4E88320004; Tue, 5 Nov 2019 19:03:46 +0000 (UTC) Date: Tue, 5 Nov 2019 20:03:44 +0100 From: Miquel Raynal To: Kamal Dasu Subject: Re: [PATCH] mtd: set mtd partition panic write flag Message-ID: <20191105200344.1e8c3eab@xps13> In-Reply-To: <20191021193343.41320-1-kdasu.kdev@gmail.com> References: <20191021193343.41320-1-kdasu.kdev@gmail.com> Organization: Bootlin X-Mailer: Claws Mail 3.17.3 (GTK+ 2.24.32; x86_64-pc-linux-gnu) MIME-Version: 1.0 X-CRM114-Version: 20100106-BlameMichelson ( TRE 0.8.0 (BSD) ) MR-646709E3 X-CRM114-CacheID: sfid-20191105_110350_836277_1C0764AA X-CRM114-Status: GOOD ( 18.03 ) X-BeenThere: linux-mtd@lists.infradead.org X-Mailman-Version: 2.1.29 Precedence: list List-Id: Linux MTD discussion mailing list List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Cc: Vignesh Raghavendra , Richard Weinberger , linux-kernel@vger.kernel.org, Marek Vasut , bcm-kernel-feedback-list@broadcom.com, linux-mtd@lists.infradead.org, Brian Norris , David Woodhouse Content-Type: text/plain; charset="utf-8" Content-Transfer-Encoding: base64 Sender: "linux-mtd" Errors-To: linux-mtd-bounces+linux-mtd=archiver.kernel.org@lists.infradead.org SGkgS2FtYWwsCgpSaWNoYXJkLCBzb21ldGhpbmcgdG8gbG9vayBpbnRvIGJlbG93IDopCgpLYW1h bCBEYXN1IDxrZGFzdS5rZGV2QGdtYWlsLmNvbT4gd3JvdGUgb24gTW9uLCAyMSBPY3QgMjAxOSAx NTozMjo1MgotMDQwMDoKCj4gQ2hlY2sgbXRkIHBhbmljIHdyaXRlIGZsYWcgYW5kIHNldCB0aGUg bXRkIHBhcnRpdGlvbiBwYW5pYwo+IHdyaXRlIGZsYWcgc28gdGhhdCBsb3cgbGV2ZWwgZHJpdmVy cyBjYW4gdXNlIGl0IHRvIHRha2UKPiByZXF1aXJlZCBhY3Rpb24gdG8gZW5zdXJlIG9vcHMgZGF0 YSBnZXRzIHdyaXR0ZW4gdG8gYXNzaWduZWQKPiBtdGQgcGFydGl0aW9uLgoKSSBmZWVsIHRoZXJl IGlzIHNvbWV0aGluZyB3cm9uZyB3aXRoIHRoZSBjdXJyZW50IGltcGxlbWVudGF0aW9uCnJlZ2Fy ZGluZyBwYXJ0aXRpb25zIGJ1dCBJIGFtIG5vdCBzdXJlIHRoaXMgaXMgdGhlIHJpZ2h0IGZpeC4g SXMgdGhpcwpzb21ldGhpbmcgeW91IGRldGVjdGVkIHdpdGggc29tZSBraW5kIG9mIHN0YXRpYyBj aGVja2VyIG9yIGRpZCB5b3UKYWN0dWFsbHkgZXhwZXJpZW5jZSBhbiBpc3N1ZT8KCkluIHRoZSBj b21taXQgbG9nIHlvdSBzYXkgImNoZWNrIG10ZCAoSSBzdXBwb3NlIHlvdSBtZWFuIHRoZQptYXN0 ZXIpIHBhbmljIHdyaXRlIGZsYWcgYW5kIHNldCB0aGUgbXRkIHBhcnRpdGlvbiBwYW5pYyB3cml0 ZSBmbGFnIgp3aGljaCBtYWtlcyBzZW5zZSwgYnV0IGluIHJlYWxpdHkgbXkgdW5kZXJzdGFuZGlu ZyBpcyB0aGF0IHlvdSBkbyB0aGUKb3Bwb3NpdGU6IHlvdSBjaGVjayBtdGQtPm9vcHNfcGFuaWNf d3JpdGUgd2hpY2ggaXMgdGhlIHBhcnRpdGlvbnMnCnN0cnVjdHVyZSwgYW5kIHNldCBwYXJ0LT5w YXJlbnQtPm9vcHNfcGFuaWNfd3JpdGUgd2hpY2ggaXMgdGhlIG1hc3RlcidzCmZsYWcuCgpBbHNv LCBJIGFtIG5vdCBzdXJlIGlmIGl0IGlzIHdvcnRoIGNoZWNraW5nIGFueXRoaW5nLCB3aHkgbm90 IGp1c3Qgc2V0Cm10ZC0+b29wc19wYW5pY193cml0ZSBpbiB0aGlzIGZ1bmN0aW9uPwoKU2FtZSBj b21tZW50IGZvciB0aGUgLWFscmVhZHkgZXhpc3RpbmctIGNvbmRpdGlvbiBpbiBtdGRfcGFuaWNf d3JpdGUuCkFzIHNvb24gYXMgd2UgYXJlIGluIHRoZXNlIGZ1bmN0aW9ucywgd2Uga25vdyB0aGVy ZSBpcyBhIHBhbmljLCByaWdodD8KU28gd2h5IGNoZWNraW5nIGlmIHRoZSBiaXQgaXMgYWxyZWFk eSBzZXQgYmVmb3JlIGZvcmNpbmcgaXQ/Cgo+IAo+IEZpeGVzOiA5Zjg5N2JmZGQ4ICgibXRkOiBB ZGQgZmxhZyB0byBpbmRpY2F0ZSBwYW5pY193cml0ZSIpCj4gU2lnbmVkLW9mZi1ieTogS2FtYWwg RGFzdSA8a2Rhc3Uua2RldkBnbWFpbC5jb20+Cj4gLS0tCj4gIGRyaXZlcnMvbXRkL210ZHBhcnQu YyB8IDQgKysrKwo+ICAxIGZpbGUgY2hhbmdlZCwgNCBpbnNlcnRpb25zKCspCj4gCj4gZGlmZiAt LWdpdCBhL2RyaXZlcnMvbXRkL210ZHBhcnQuYyBiL2RyaXZlcnMvbXRkL210ZHBhcnQuYwo+IGlu ZGV4IDczMjhjMDY2YzViYS4uYjRmNjQ3OWFiZWRhIDEwMDY0NAo+IC0tLSBhL2RyaXZlcnMvbXRk L210ZHBhcnQuYwo+ICsrKyBiL2RyaXZlcnMvbXRkL210ZHBhcnQuYwo+IEBAIC0xNTksNiArMTU5 LDEwIEBAIHN0YXRpYyBpbnQgcGFydF9wYW5pY193cml0ZShzdHJ1Y3QgbXRkX2luZm8gKm10ZCwg bG9mZl90IHRvLCBzaXplX3QgbGVuLAo+ICAJCXNpemVfdCAqcmV0bGVuLCBjb25zdCB1X2NoYXIg KmJ1ZikKPiAgewo+ICAJc3RydWN0IG10ZF9wYXJ0ICpwYXJ0ID0gbXRkX3RvX3BhcnQobXRkKTsK PiArCj4gKwlpZiAobXRkLT5vb3BzX3BhbmljX3dyaXRlKQo+ICsJCXBhcnQtPnBhcmVudC0+b29w c19wYW5pY193cml0ZSA9IHRydWU7Cj4gKwo+ICAJcmV0dXJuIHBhcnQtPnBhcmVudC0+X3Bhbmlj X3dyaXRlKHBhcnQtPnBhcmVudCwgdG8gKyBwYXJ0LT5vZmZzZXQsIGxlbiwKPiAgCQkJCQkgIHJl dGxlbiwgYnVmKTsKPiAgfQoKVGhhbmtzLApNaXF1w6hsCgpfX19fX19fX19fX19fX19fX19fX19f X19fX19fX19fX19fX19fX19fX19fX19fX19fX19fX18KTGludXggTVREIGRpc2N1c3Npb24gbWFp bGluZyBsaXN0Cmh0dHA6Ly9saXN0cy5pbmZyYWRlYWQub3JnL21haWxtYW4vbGlzdGluZm8vbGlu dXgtbXRkLwo=