public inbox for glibc-bugs@sourceware.org help / color / mirror / Atom feed
From: "i at maskray dot me" <sourceware-bugzilla@sourceware.org> To: glibc-bugs@sourceware.org Subject: [Bug dynamic-link/28676] p_align on PT_LOAD segment in DSO isn't honored Date: Tue, 14 Dec 2021 05:31:41 +0000 [thread overview] Message-ID: <bug-28676-131-xnCiF9frwM@http.sourceware.org/bugzilla/> (raw) In-Reply-To: <bug-28676-131@http.sourceware.org/bugzilla/> https://sourceware.org/bugzilla/show_bug.cgi?id=28676 Fangrui Song <i at maskray dot me> changed: What |Removed |Added ---------------------------------------------------------------------------- CC| |i at maskray dot me --- Comment #3 from Fangrui Song <i at maskray dot me> --- This is not a bug per se. My reasoning is at https://sourceware.org/pipermail/libc-alpha/2021-December/134121.html `__attribute__((aligned(0x200000))) = 1;` does not necessarily mean the large alignment needs to be satisfied on a system with a smaller page size. Now "elf: Properly align PT_LOAD segments [BZ #28676]" overaligns memory mappings to p_align to make the use case work. It's a new feature, not a bugfix. The 2020 kernel commit https://git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux.git/commit/?id=ce81bb256a224259ab686742a6284930cbe4f1fa has no waste, so it is more justifiable. The emulation in ld.so, however, would incur significant overhead, so it needs more thoughts. At the very least, the max-page-size=0x200000 for -z noseparate-code on x86-64 may be problematic. It looks like we need more thoughts how tools like objcopy and ld can make the cost small, or whether such changes are justifiable. -- You are receiving this mail because: You are on the CC list for the bug.
next prev parent reply other threads:[~2021-12-14 5:31 UTC|newest] Thread overview: 13+ messages / expand[flat|nested] mbox.gz Atom feed top 2021-12-08 23:51 [Bug dynamic-link/28676] New: " hjl.tools at gmail dot com 2021-12-09 1:11 ` [Bug dynamic-link/28676] " hjl.tools at gmail dot com 2021-12-10 19:45 ` hjl.tools at gmail dot com 2021-12-13 15:00 ` fweimer at redhat dot com 2021-12-13 15:00 ` fweimer at redhat dot com 2021-12-13 15:02 ` fweimer at redhat dot com 2021-12-13 23:36 ` sam at gentoo dot org 2021-12-14 5:31 ` i at maskray dot me [this message] 2021-12-15 22:25 ` hjl.tools at gmail dot com 2022-01-05 13:32 ` hjl.tools at gmail dot com 2022-01-05 13:32 ` hjl.tools at gmail dot com 2022-01-21 19:43 ` cvs-commit at gcc dot gnu.org 2022-01-24 14:52 ` hjl.tools at gmail dot com
Reply instructions: You may reply publicly to this message via plain-text email using any one of the following methods: * Save the following mbox file, import it into your mail client, and reply-to-all from there: mbox Avoid top-posting and favor interleaved quoting: https://en.wikipedia.org/wiki/Posting_style#Interleaved_style * Reply using the --to, --cc, and --in-reply-to switches of git-send-email(1): git send-email \ --in-reply-to=bug-28676-131-xnCiF9frwM@http.sourceware.org/bugzilla/ \ --to=sourceware-bugzilla@sourceware.org \ --cc=glibc-bugs@sourceware.org \ /path/to/YOUR_REPLY https://kernel.org/pub/software/scm/git/docs/git-send-email.html * If your mail client supports setting the In-Reply-To header via mailto: links, try the mailto: linkBe sure your reply has a Subject: header at the top and a blank line before the message body.
This is a public inbox, see mirroring instructions for how to clone and mirror all data and code used for this inbox; as well as URLs for read-only IMAP folder(s) and NNTP newsgroup(s).