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=-7.2 required=3.0 tests=BAYES_00,DKIM_SIGNED, DKIM_VALID,FREEMAIL_FORGED_FROMDOMAIN,FREEMAIL_FROM, HEADER_FROM_DIFFERENT_DOMAINS,INCLUDES_PATCH,MAILING_LIST_MULTI,NICE_REPLY_A, SPF_HELO_NONE,SPF_PASS,URIBL_BLOCKED,USER_AGENT_SANE_1 autolearn=no 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 395FAC4361B for ; Thu, 17 Dec 2020 19:17:30 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id D703E239ED for ; Thu, 17 Dec 2020 19:17:29 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1728684AbgLQTR3 (ORCPT ); Thu, 17 Dec 2020 14:17:29 -0500 Received: from mout.gmx.net ([212.227.15.18]:54759 "EHLO 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<816c1571b4132f991089b40a759cf68afcf4af43.camel@perches.com> From: Helge Deller Autocrypt: addr=deller@gmx.de; keydata= mQINBF3Ia3MBEAD3nmWzMgQByYAWnb9cNqspnkb2GLVKzhoH2QD4eRpyDLA/3smlClbeKkWT HLnjgkbPFDmcmCz5V0Wv1mKYRClAHPCIBIJgyICqqUZo2qGmKstUx3pFAiztlXBANpRECgwJ r+8w6mkccOM9GhoPU0vMaD/UVJcJQzvrxVHO8EHS36aUkjKd6cOpdVbCt3qx8cEhCmaFEO6u CL+k5AZQoABbFQEBocZE1/lSYzaHkcHrjn4cQjc3CffXnUVYwlo8EYOtAHgMDC39s9a7S90L 69l6G73lYBD/Br5lnDPlG6dKfGFZZpQ1h8/x+Qz366Ojfq9MuuRJg7ZQpe6foiOtqwKym/zV dVvSdOOc5sHSpfwu5+BVAAyBd6hw4NddlAQUjHSRs3zJ9OfrEx2d3mIfXZ7+pMhZ7qX0Axlq Lq+B5cfLpzkPAgKn11tfXFxP+hcPHIts0bnDz4EEp+HraW+oRCH2m57Y9zhcJTOJaLw4YpTY GRUlF076vZ2Hz/xMEvIJddRGId7UXZgH9a32NDf+BUjWEZvFt1wFSW1r7zb7oGCwZMy2LI/G aHQv/N0NeFMd28z+deyxd0k1CGefHJuJcOJDVtcE1rGQ43aDhWSpXvXKDj42vFD2We6uIo9D 1VNre2+uAxFzqqf026H6cH8hin9Vnx7p3uq3Dka/Y/qmRFnKVQARAQABtBxIZWxnZSBEZWxs ZXIgPGRlbGxlckBnbXguZGU+iQJRBBMBCAA7AhsDBQsJCAcCBhUKCQgLAgQWAgMBAh4BAheA FiEERUSCKCzZENvvPSX4Pl89BKeiRgMFAl3J1zsCGQEACgkQPl89BKeiRgNK7xAAg6kJTPje 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KkjlZb7QsNatuPMxGRmaGNKtXeZZYEAo92paKaqBgV839lRgEZRTDmK8YxQIZWwuC5Pcspr47 QFe8gJT+RDZoCkd93CQwNqAeMu8YnDni5qyqZWQJTKk8GRCN0tPA8e3hMPNwrLYktWup97JG2 USRfCZWCenk3HfjgZCcW6+3xAxtSdiuXwIuoXMi6c/J0n4T6bZNI2LY5/xZHMeudGaS3uDekm jIB5IFjGgU194tOaBQolTRwjaEJjFdVkJtJdMoI1j1S7V0TG12JRwdr4MD3ANUKCfOtIy4eA+ pKnIWBldis8YWnqvfGePMylgDbDxX7FLLOQPYkRU4URIDEPAoljPv34+hztchs7A0jUJPCWYs kXTOSI4DPl/oxNEaJATwAMhwYgjdY5PRiLpVb5O/Enjk9uxRf2fh53Vc6odZhspuuzQg8/MaR TdGWUyG0omDXbNAyfyzpnWwdSrQgFYbjg1wsx6oOdw758Mdz9FXkQzhxnSPjxabZ0AZXJw8wD lK4GMkP1jHiJloTsGiqsLE7WLMt+fQjDXtRrJAnImgkrZLVbujukKFpu76POVDq3gsLWRs/cL v3BJSeUGtoWZgn/4uYSR0S4HayIkb/hikR7vVsjCR8r9c9myoBHcDiDnjkAI3yYwuQ3J308Qe 03g2r67Bkd9CicMK/Qo0iGsg/Ic9Raa6BgyRUYIz8fudLSzoN4I8SgX3YpS/zYMDDmrIUpgug loU0z/YXSY0zIDj85hOPqmxZAUDYwfRxCcrrO/9AECER+4VpKnDWy26vidQZONzhGvs48gK1N ZfgMXLezfW20Qrvd/Kamwl36TDR36K4mOAfDQktW6YvQv3B7CljkqXlS0rZQY8EcmAbYScpVr wIdnEusDOIM6ph9jcd4g== Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org On 12/17/20 7:15 PM, Joe Perches wrote: > On Thu, 2020-12-17 at 18:42 +0100, Helge Deller wrote: >> On 12/17/20 6:27 PM, Joe Perches wrote: >>> On Thu, 2020-12-17 at 18:11 +0100, Helge Deller wrote: >>>> In most cases people use lookup_symbol_name() to resolve a kernel sym= bol >>>> and then print it via printk(). >>>> >>>> In such cases using the %ps, %pS, %pSR or %pB printk formats are easi= er >>>> to use and thus should be preferred. >>> [] >>>> diff --git a/scripts/checkpatch.pl b/scripts/checkpatch.pl >>> [] >>>> @@ -4317,6 +4317,12 @@ sub process { >>>> =C2=A0 "LINUX_VERSION_CODE should be avoided, code should be f= or the version to which it is merged\n" . $herecurr); >>>> =C2=A0 } >>>> >>>> +# avoid lookup_symbol_name() >>>> + if ($line =3D~ /\blookup_symbol_name\b/) { >>>> + WARN("PREFER_PRINTK_FORMAT", >>>> + "If possible prefer %ps or %pS printk format string to print= symbol name instead of using lookup_symbol_name()\n" . $herecurr); >>>> + } >>>> + >>>> =C2=A0# check for uses of printk_ratelimit >>>> =C2=A0 if ($line =3D~ /\bprintk_ratelimit\s*\(/) { >>>> =C2=A0 WARN("PRINTK_RATELIMITED", >>> >>> Huh? nak. >>> >>> lookup_symbol_name is used in the kernel a grand total of 3 times. >> >> Yes, there were much more in the past which got fixed by patches I subm= itted. > > Hi Helge. > > Much more may be a bit of an overstatement. > > I found 3 instances of lookup_symbol_name removals in 2 patches. > > commit 36dbca148bf8e3b8658982aa2256bdc7ef040256 > - lookup_symbol_name((ulong)pm_power_off, symname); > - lookup_symbol_name((ulong)pm_power_off, symname); > commit da88f9b3113620dcd30fc203236aa53d5430ee98 > - if (lookup_symbol_name((unsigned long)sym, symname) < 0) > > There's a tension between adding tests and newbies that consider > checkpatch warnings as dicta that must be followed so there would > be patches submitted eventually against the existing correct uses. > > So thanks, but given the very few existing all correct uses of > this function and the low probability of new uses I'd prefer not > to apply this. Ok. Thanks! Helge