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=-5.3 required=3.0 tests=DKIM_SIGNED,DKIM_VALID, DKIM_VALID_AU,FREEMAIL_FORGED_FROMDOMAIN,FREEMAIL_FROM, HEADER_FROM_DIFFERENT_DOMAINS,INCLUDES_PATCH,MAILING_LIST_MULTI,SPF_HELO_NONE, SPF_PASS,USER_AGENT_SANE_1 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 D927DC10F29 for ; Tue, 17 Mar 2020 08:22:44 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.kernel.org (Postfix) with ESMTP id AD0B2205ED for ; Tue, 17 Mar 2020 08:22:44 +0000 (UTC) Authentication-Results: mail.kernel.org; dkim=pass (2048-bit key) header.d=gmail.com header.i=@gmail.com header.b="tt+YF24j" Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1725943AbgCQIWn (ORCPT ); Tue, 17 Mar 2020 04:22:43 -0400 Received: from mail-pl1-f196.google.com ([209.85.214.196]:38771 "EHLO mail-pl1-f196.google.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1725536AbgCQIWn (ORCPT ); Tue, 17 Mar 2020 04:22:43 -0400 Received: by mail-pl1-f196.google.com with SMTP id w3so9302125plz.5 for ; Tue, 17 Mar 2020 01:22:42 -0700 (PDT) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=gmail.com; s=20161025; h=date:from:to:cc:subject:message-id:references:mime-version :content-disposition:content-transfer-encoding:in-reply-to :user-agent; bh=S2YGO8hzm/1fcL5wpw6053JutNwav0C8AiM1n0QLEJQ=; b=tt+YF24jXkH4DM2UPX3by871WLRY4lJS9/PgQ3JcC+pZiDfqTI72Toa0UhnV1blIER ferVEZVuDowmSFATTGRgXZzaiabKPqIr8sXX3jEOKI4eODGwy3kPCLqB0RgdmqpNp3ub FUF60dlbYzcD3jtnlbyEBnJ0/Yv8FDwqp4Ci9JUMUXKYx0jRMZCPsd0aBuKrFMkhd4pz JsifRxQLQ0I/Um+E/9vxEblk74TyqRhKZXdmYqaxXglJlCUZKWPXc38U3jdG5RdRILSS mwM+BeUDnJwARYv1wXCrfU92TZIxOo47fEp6t3C+Ol9dHGmu/WmOhy5Qe8LkoGQ+isn+ zOUQ== X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20161025; h=x-gm-message-state:date:from:to:cc:subject:message-id:references :mime-version:content-disposition:content-transfer-encoding :in-reply-to:user-agent; bh=S2YGO8hzm/1fcL5wpw6053JutNwav0C8AiM1n0QLEJQ=; b=HpbfLZyIy/mVeM/ME2crwOriTd8VdGqDZK5MzEPb12RYB84SrKj4mcoiq8SpPVQzFy +nMBN+gEihkhXfAa5pwRRSrRf2gxmZNsrv37fdudNzvXCzGX1TXiM/fdHwiKwzrEBg5r ws5whMOd4medw7F68fZvVMPM2qrYvBLlqO1Z8G7r4slo7cVbuUTxmWY2uFhaYpGKZsBq exg4R5bB94VHAh8kBIgBPgj2q8HldPmZQy3HFuejlQ018yDhArnrwubTQpAcezJ4zU31 /sVFVx9czhn0wwUEb7+DLgH6PsCPbdalGVofqflhHwvdbeGyJzKZWe5OF7VwF41hxQp+ H7jg== X-Gm-Message-State: ANhLgQ36rqTDGP1xSJeWhB3kJXUQBsMxe94D+eeevnUc6TxUpLzkJddu wluqhJULW9mssceZJ1IYaNE= X-Google-Smtp-Source: ADFU+vvcUoxwSV/QfKtwuyZl9nq8hzXjTUPjOPwh177PntOmiNmWzrBdoV0eRhfNJ/Vn83jYM7xjug== X-Received: by 2002:a17:902:a9c5:: with SMTP id b5mr3274017plr.126.1584433362206; Tue, 17 Mar 2020 01:22:42 -0700 (PDT) Received: from localhost ([2401:fa00:8f:203:5bbb:c872:f2b1:f53b]) by smtp.gmail.com with ESMTPSA id s25sm2132325pfe.147.2020.03.17.01.22.40 (version=TLS1_3 cipher=TLS_AES_256_GCM_SHA384 bits=256/256); Tue, 17 Mar 2020 01:22:41 -0700 (PDT) Date: Tue, 17 Mar 2020 17:22:39 +0900 From: Sergey Senozhatsky To: Shreyas Joshi Cc: Sergey Senozhatsky , Steven Rostedt , "pmladek@suse.com" , "sergey.senozhatsky@gmail.com" , "shreyasjoshi15@gmail.com" , "linux-kernel@vger.kernel.org" Subject: Re: [PATCH] printk: handle blank console arguments passed in. Message-ID: <20200317082239.GA4494@google.com> References: <20200309052915.858-1-shreyas.joshi@biamp.com> <20200316213900.6b1eb594@oasis.local.home> <20200317020144.GB219881@google.com> <20200317021736.syreot6rs5rtqsh3@shreyas_biamp.biamp.com> MIME-Version: 1.0 Content-Type: text/plain; charset=utf-8 Content-Disposition: inline Content-Transfer-Encoding: 8bit In-Reply-To: <20200317021736.syreot6rs5rtqsh3@shreyas_biamp.biamp.com> User-Agent: Mutt/1.12.2 (2019-09-21) Sender: linux-kernel-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org On (20/03/16 19:17), Shreyas Joshi wrote: > > Thanks! I thought If we put a warning there then it won’t print anything. > Please advise. I will send a new patch with the line wrapping to at most 75 once > I know if I need to change anything more. > What I'm thinking about is turning "param=\0" into invalid case, not just for printk(), for in general. Treat it as a NULL value. Something like this, perhaps? --- init/main.c | 4 ++++ lib/cmdline.c | 8 ++++++-- 2 files changed, 10 insertions(+), 2 deletions(-) diff --git a/init/main.c b/init/main.c index d46b5673ecb4..46b732cd2615 100644 --- a/init/main.c +++ b/init/main.c @@ -673,6 +673,10 @@ static int __init do_early_param(char *param, char *val, (strcmp(param, "console") == 0 && strcmp(p->str, "earlycon") == 0) ) { + if (!val && strchr(p->str, '=')) { + pr_warn("Malformed early option '%s'\n", param); + continue; + } if (p->setup_func(val) != 0) pr_warn("Malformed early option '%s'\n", param); } diff --git a/lib/cmdline.c b/lib/cmdline.c index fbb9981a04a4..33fa0fc505a0 100644 --- a/lib/cmdline.c +++ b/lib/cmdline.c @@ -222,9 +222,9 @@ char *next_arg(char *args, char **param, char **val) } *param = args; - if (!equals) + if (!equals) { *val = NULL; - else { + } else { args[equals] = '\0'; *val = args + equals + 1; @@ -244,6 +244,10 @@ char *next_arg(char *args, char **param, char **val) } else next = args + i; + /* Treat blank param value, e.g. 'param=', as NULL value. */ + if (equals && **val == '\0') + *val = NULL; + /* Chew up trailing spaces. */ return skip_spaces(next); } -- 2.25.1.481.gfbce0eb801-goog