diff options
author | https://me.yahoo.com/a/g3Ccalpj0NhN566pHbUl6i9QF0QEkrhlfPM-#b1c14 <diana@web> | 2015-02-16 20:08:03 +0100 |
---|---|---|
committer | GNU Hurd web pages engine <web-hurd@gnu.org> | 2015-02-16 20:08:03 +0100 |
commit | 95878586ec7611791f4001a4ee17abf943fae3c1 (patch) | |
tree | 847cf658ab3c3208a296202194b16a6550b243cf /open_issues/glibc/t/tls.mdwn | |
parent | 8063426bf7848411b0ef3626d57be8cb4826715e (diff) | |
download | web-95878586ec7611791f4001a4ee17abf943fae3c1.tar.gz web-95878586ec7611791f4001a4ee17abf943fae3c1.tar.bz2 web-95878586ec7611791f4001a4ee17abf943fae3c1.zip |
rename open_issues.mdwn to service_solahart_jakarta_selatan__082122541663.mdwn
Diffstat (limited to 'open_issues/glibc/t/tls.mdwn')
-rw-r--r-- | open_issues/glibc/t/tls.mdwn | 81 |
1 files changed, 0 insertions, 81 deletions
diff --git a/open_issues/glibc/t/tls.mdwn b/open_issues/glibc/t/tls.mdwn deleted file mode 100644 index b10703fd..00000000 --- a/open_issues/glibc/t/tls.mdwn +++ /dev/null @@ -1,81 +0,0 @@ -[[!meta copyright="Copyright © 2011, 2012, 2013 Free Software Foundation, -Inc."]] - -[[!meta license="""[[!toggle id="license" text="GFDL 1.2+"]][[!toggleable -id="license" text="Permission is granted to copy, distribute and/or modify this -document under the terms of the GNU Free Documentation License, Version 1.2 or -any later version published by the Free Software Foundation; with no Invariant -Sections, no Front-Cover Texts, and no Back-Cover Texts. A copy of the license -is included in the section entitled [[GNU Free Documentation -License|/fdl]]."]]"""]] - -[[!tag open_issue_glibc open_issue_libpthread]] - -# To Do - - * Discuss d2431f633e6139a62e1575ec18830f7e81160cf0 with Samuel. - - * Validate our implementation against - <https://sourceware.org/glibc/wiki/TLSandSignals>. - - -# Documentation - -[[!taglink open_issue_documentation]] - - * IRC, freenode, #hurd, 2011-11-26 - - <tschwinge> In glibc multiarch support (strcasecmp for i686 SSE3, etc.) - there is access to memory via gs: -- this will need to be changed for - us, right? - <youpi> depends on the access - <tschwinge> * `optimized strcasecmp and strncasecmp for x86-32` - (multiarch), - <tschwinge> 76e3966e9efc3808a9e7ad09121c5dfc1211c20b + - <tschwinge> 6abf346582ba678f4850a88b4a5950593841df1d + - <tschwinge> 5583a0862cf94f71cbcde91c4043a20af65facca. `gs` - access. - <youpi> + movl __libc_tsd_LOCALE@GOTNTPOFF(%ebx), %eax - <youpi> that's handled by the linker fine - <youpi> it's only the things held in the tcb_t structure which can pose - problem - <tschwinge> tcbhead_t? - <tschwinge> I'm looking at this. - <tschwinge> So, at gs:0, there is the TCB. - <tschwinge> And we have the same layout as NPTL/Linux, just that we - don't have as much data there as they have. - <tschwinge> We're missing multiple_threads, sysinfo, sttack_guard, - pointer_guard, gscope_flag, private_futex, __private_tm[5]. - <tschwinge> So, if one of these is referenced (be it my name or by - numeric offset), this is invalid for us. - <tschwinge> Anything else should work equivalently. - <youpi> yes - <youpi> usually the only numeric offset being used is 0 - <youpi> so it would simply not build - <tschwinge> And the other offsers are generated via tcb-offsets.sym. - <tschwinge> glibc's elf/stackguard-macros.h is wrong for us (but not - used anywhere apart from elf/tst-stackguard1.c, I think). - -After commit a9538892adfbb9f092e0bb14ff3a1703973968af, it's -`sysdeps/i386/stackguard-macros.h`; problem remains. - - <tschwinge> __thread __locale_t __libc_tsd_LOCALE = &_nl_global_locale; - -- this means that a __libc_tsd_LOCALE values will be in the TLS - segment, and this is what is being accessed from the assembler code - with %gs:__libc_tsd_LOCALE@NTPOFF, and the linker will resolve this. - <youpi> yes - <youpi> see in the nm output, the libc_tsd symbols - <youpi> these provide the offsets - <tschwinge> youpi: Thank you, I'm now understanding this part of TLS - much better. - <youpi> have you had a look at the tls.pdf from Uli ? - <youpi> all the gory details are there :) - -Commit c61b4d41c9647a54a329aa021341c0eb032b793e, [[!sourceware_PR 15754]], adds -`sysdeps/i386/stackguard-macros.h:POINTER_CHK_GUARD`, which is not correct for -us (at the moment), but it also shouldn't cause any harm, as this file is only -used in `elf/tst-ptrguard1.c` and `elf/tst-stackguard1.c`, which now will fail -to build for us, as we don't have a `pointer_guard` member in -`sysdeps/mach/hurd/tls.h:tcbhead_t`. - -We don't define `THREAD_SET_POINTER_GUARD`. |