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 BC870EE49A0 for ; Fri, 25 Aug 2023 21:10:44 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S229566AbjHYVKO (ORCPT ); Fri, 25 Aug 2023 17:10:14 -0400 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:37458 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S231352AbjHYVJr (ORCPT ); Fri, 25 Aug 2023 17:09:47 -0400 Received: from mout.gmx.net (mout.gmx.net [212.227.15.18]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id E2F6C211E; Fri, 25 Aug 2023 14:09:44 -0700 (PDT) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=gmx.de; s=s31663417; t=1692997782; x=1693602582; i=deller@gmx.de; bh=t9bxSjK12LeGCsmisqAXpIIyjCQZXoB1R6YMQj1H2HE=; 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linux-kernel@vger.kernel.org, Andrei Vagin , linux-parisc References: <20230822113453.acc69f8540bed25cde79e675@linux-foundation.org> <8eb38faf-16a2-a538-b243-1b4706f73169@gmx.de> In-Reply-To: Content-Type: text/plain; charset=UTF-8; format=flowed Content-Transfer-Encoding: quoted-printable X-Provags-ID: V03:K1:pgE4+/iNO0aZYR+fzWXyvjMkNs3h2BleANDINF8q2LmPadMpRcA Nxxi8U7KzoF8wOSEgScVK8/1WXSQ4keaDmoOjhoPUDxlgQsPe2XHEeRP9aLNdR1eKezTveB PZipSe2pFhrldUsZPB/UslmB68RtMqUPY5fJENvxGJZJ8/CMKbC2Mh8f/o7d0srSWsxTuvN +sPsQpIsC/wtj52UmqRsQ== UI-OutboundReport: notjunk:1;M01:P0:4dNZi+3V608=;0kgLbPPTQEtBxVBcOBBz7lLhB+l QEQaQ58OslxI8G1BwP/iCmm4afXPep2x1Pk0T09w+LLzqm/dZtiow1nlsTc/L++FNTRPhwbXx 1iExaAGEZMpmIrLn5ho+xY+Ex3K4T2+yJAMFWkkIjWQPbK6HjM7ZaSXNHJERcmQEov/rh0C+1 T6+n5AOKuuTu9IKcYXuwYa4pcYrgeH5AgQlMtatXC5dXr9dXtF1Ez/Bsrd3LdO5S3wtrBtu0N w0VMwBylVE9QqL0DlMBcn5tUfjHeaFSCxQbmr+992Hd6DDc/46fMA8WZnd9OOMhO5sZIJL0Nk J4xX3tPrGYQf5uEfhuGwHS/wJzAfbVRZBflZfBH1f66zb3GIQZcq1xZcOCrxo97x8VYW8elb4 iPpF2AnB3bnHO7n/Oa4dq0YTYkMPVbJSu2FN4pLDtAUuurnrKuIA9Em+yF1UGT8EnrjmbBIN9 u5zYMlD0Ft2RtGnQfUF2J9wDN91dg8wLDEqqfPdFAGV8LJCwjR0KIIzX+Wc4OEgJ/f/42qhJv WK1oIqWjdMkxgHE9ds0ZIRbAeGmLDyhuIpqnUSYKJEQOT0VqbCnCS+Krdkn9MDTZ7yVPRhTcY oxpan1EB1cJNBVcmthp2OzhI2LK2C0xotgolUbJsF3N2dFdp9RNFJ+epF9dntEvbWYZWddoIa AXBjtMJObP2bt4yr6LhQUgd5oE2JrSkGZ8FaJcV5+n0TFMcTFE2vedAaVfDjwD7clyJSo/dy+ iXQRX28IuYjJ2Hmy70QySyVY5+D+uYuWqZ/PIrjQKwFC8PXJpqODqp99MtdZuCrkZcgJtgojt KURKVFGfFpC9MGd/XftLjnOOhW/5Q9rB8RMiKi3kSO/PkWo3UQ0huqq1EqEoFe90VUjVffEVl qDVawubySS09uekF15tI7GnBp+ol4x6myobbZupmkuetYD3OKNw3hesKcwvLvFTGghAwRmO2/ D6NWiH6Ki0+GGu7Sk8PpTJeUbdE= Precedence: bulk List-ID: X-Mailing-List: linux-parisc@vger.kernel.org On 8/23/23 00:04, Helge Deller wrote: > On 8/22/23 22:53, Helge Deller wrote: >> On 8/22/23 20:34, Andrew Morton wrote: >>> On Tue, 22 Aug 2023 11:20:36 +0200 Helge Deller wrote: >>> >>>> On a 32-bit kernel addresses should be shown with 8 hex digits, e.g.: >>>> >>>> root@debian:~# cat /proc/self/maps >>>> 00010000-00019000 r-xp 00000000 08:05 787324=C2=A0=C2=A0=C2=A0=C2=A0 = /usr/bin/cat >>>> 00019000-0001a000 rwxp 00009000 08:05 787324=C2=A0=C2=A0=C2=A0=C2=A0 = /usr/bin/cat >>>> 0001a000-0003b000 rwxp 00000000 00:00 0=C2=A0=C2=A0=C2=A0=C2=A0=C2=A0= =C2=A0=C2=A0=C2=A0=C2=A0 [heap] >>>> f7551000-f770d000 r-xp 00000000 08:05 794765=C2=A0=C2=A0=C2=A0=C2=A0 = /usr/lib/hppa-linux-gnu/libc.so.6 >>>> f770d000-f770f000 r--p 001bc000 08:05 794765=C2=A0=C2=A0=C2=A0=C2=A0 = /usr/lib/hppa-linux-gnu/libc.so.6 >>>> f770f000-f7714000 rwxp 001be000 08:05 794765=C2=A0=C2=A0=C2=A0=C2=A0 = /usr/lib/hppa-linux-gnu/libc.so.6 >>>> f7d39000-f7d68000 r-xp 00000000 08:05 794759=C2=A0=C2=A0=C2=A0=C2=A0 = /usr/lib/hppa-linux-gnu/ld.so.1 >>>> f7d68000-f7d69000 r--p 0002f000 08:05 794759=C2=A0=C2=A0=C2=A0=C2=A0 = /usr/lib/hppa-linux-gnu/ld.so.1 >>>> f7d69000-f7d6d000 rwxp 00030000 08:05 794759=C2=A0=C2=A0=C2=A0=C2=A0 = /usr/lib/hppa-linux-gnu/ld.so.1 >>>> f7ea9000-f7eaa000 r-xp 00000000 00:00 0=C2=A0=C2=A0=C2=A0=C2=A0=C2=A0= =C2=A0=C2=A0=C2=A0=C2=A0 [vdso] >>>> f8565000-f8587000 rwxp 00000000 00:00 0=C2=A0=C2=A0=C2=A0=C2=A0=C2=A0= =C2=A0=C2=A0=C2=A0=C2=A0 [stack] >>>> >>>> But since commmit 0e3dc0191431 ("procfs: add seq_put_hex_ll to speed = up >>>> /proc/pid/maps") even on native 32-bit kernels the output looks like = this: >>>> >>>> root@debian:~# cat /proc/self/maps >>>> 0000000010000-0000000019000 r-xp 00000000 000000008:000000005 787324= =C2=A0 /usr/bin/cat >>>> 0000000019000-000000001a000 rwxp 000000009000 000000008:000000005 787= 324=C2=A0 /usr/bin/cat >>>> 000000001a000-000000003b000 rwxp 00000000 00:00 0=C2=A0 [heap] >>>> 00000000f73d1000-00000000f758d000 r-xp 00000000 000000008:000000005 7= 94765=C2=A0 /usr/lib/hppa-linux-gnu/libc.so.6 >>>> 00000000f758d000-00000000f758f000 r--p 000000001bc000 000000008:00000= 0005 794765=C2=A0 /usr/lib/hppa-linux-gnu/libc.so.6 >>>> 00000000f758f000-00000000f7594000 rwxp 000000001be000 000000008:00000= 0005 794765=C2=A0 /usr/lib/hppa-linux-gnu/libc.so.6 >>>> 00000000f7af9000-00000000f7b28000 r-xp 00000000 000000008:000000005 7= 94759=C2=A0 /usr/lib/hppa-linux-gnu/ld.so.1 >>>> 00000000f7b28000-00000000f7b29000 r--p 000000002f000 000000008:000000= 005 794759=C2=A0 /usr/lib/hppa-linux-gnu/ld.so.1 >>>> 00000000f7b29000-00000000f7b2d000 rwxp 0000000030000 000000008:000000= 005 794759=C2=A0 /usr/lib/hppa-linux-gnu/ld.so.1 >>>> 00000000f7e0c000-00000000f7e0d000 r-xp 00000000 00:00 0=C2=A0 [vdso] >>>> 00000000f9061000-00000000f9083000 rwxp 00000000 00:00 0=C2=A0 [stack] >>>> >>>> This patch brings back the old default 8-hex digit output for >>>> 32-bit kernels and compat tasks. >>>> >>>> Fixes: 0e3dc0191431 ("procfs: add seq_put_hex_ll to speed up /proc/pi= d/maps") >>> >>> That was five years ago.=C2=A0 Given there is some risk of breaking ex= isting >>> parsers, is it worth fixing this? >> >> Huh... that's right! >> Nevertheless, kernel 6.1.45 has it right, which isn't 5 years old. >> I don't see the reason for that change right now, so I'll need to figur= e out what changed... > > It seems to be due to a new bug in gcc's __builtin_clzll() > function (at least on parisc), which seems to return values > for "long" (32bit) instead for "long long" (64bit). > > Please ignore this patch for now. To sum up: It was a bug in the in-kernel __clzdi2() function. This patch ("lib/clz_ctz.c: Fix __clzdi2() and __ctzdi2() for 32-bit kerne= ls") fixes it: https://git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux.git/commit/= ?id=3D382d4cd1847517ffcb1800fd462b625db7b2ebea Thanks! Helge