From b1984dd2f5096fca7b7a8b93a45143825b168bda Mon Sep 17 00:00:00 2001 From: Khem Raj Date: Wed, 1 Dec 2021 22:19:33 -0800 Subject: glibc: Drop patch to support/workaround prelinked apps on armv5 The usecase explained in bug #1443 works fine now a days on qemuarmv5, tested by using lltng-ust and explicitly linking in liburcu-bp.so as well, since its no more a direct dependency of liblttng-ust.so.1 Given that usecase works, unbolt this fix now. (From OE-Core rev: 088cf642e4a58fd50f93b22b4fdf5a2f25e1ed53) Signed-off-by: Khem Raj Cc: Mark Hatle Signed-off-by: Richard Purdie --- ...bug-1443-which-explains-what-the-patch-do.patch | 58 ---------------------- meta/recipes-core/glibc/glibc_2.34.bb | 1 - 2 files changed, 59 deletions(-) delete mode 100644 meta/recipes-core/glibc/glibc/0012-Quote-from-bug-1443-which-explains-what-the-patch-do.patch (limited to 'meta') diff --git a/meta/recipes-core/glibc/glibc/0012-Quote-from-bug-1443-which-explains-what-the-patch-do.patch b/meta/recipes-core/glibc/glibc/0012-Quote-from-bug-1443-which-explains-what-the-patch-do.patch deleted file mode 100644 index 07d4411c61..0000000000 --- a/meta/recipes-core/glibc/glibc/0012-Quote-from-bug-1443-which-explains-what-the-patch-do.patch +++ /dev/null @@ -1,58 +0,0 @@ -From add514edf4299d1bf540d85d0aa0bd5fe0d46b78 Mon Sep 17 00:00:00 2001 -From: Khem Raj -Date: Wed, 18 Mar 2015 00:20:09 +0000 -Subject: [PATCH] Quote from bug 1443 which explains what the patch does : - - We build some random program and link it with -lust. When we run it, - it dies with a SIGSEGV before reaching main(). - - Libust.so depends on liburcu-bp.so from the usermode-rcu package. - Although libust.so is not prelinked, liburcu-bp.so IS prelinked; this - is critical. - - Libust.so uses a TLS / __thread variable that is defined in liburcu- - bp.so. There are special ARM-specific relocation types that allow two - shared libraries to share thread-specific data. This is critical too. - - One more critical issue: although liburcu-bp.so is prelinked, we can't - load it at its prelinked address, because we also link against - librt.so, and librt.so uses that address. - - The dynamic linker is forced to relink liburcu-bp.so at a different - address. In the course of relinking, it processes the special ARM - relocation record mentioned above. The prelinker has already filled - in the information, which is a short offset into a table of thread- - specific data that is allocated per-thread for each library that uses - TLS. Because the normal behavior of a relocation is to add the symbol - value to an addend stored at the address being relocated, we end up - adding the short offset to itself, doubling it. - - Now we have an awkward situation. The libust.so library doesn't know - about the addend, so its TLS data for this element is correct. The - liburcu-bp.so library has a different offset for the element. When we - go to initialize the element for the first time in liburcu-bp.so, we - write the address of the result at the doubled (broken) offset. - Later, when we refer to the address from libust.so, we check the value - at the correct offset, but it's NULL, so we eat hot SIGSEGV. - -Upstream-Status: Pending - -Signed-off-by: Andrei Dinu -Signed-off-by: Khem Raj ---- - sysdeps/arm/dl-machine.h | 2 +- - 1 file changed, 1 insertion(+), 1 deletion(-) - -diff --git a/sysdeps/arm/dl-machine.h b/sysdeps/arm/dl-machine.h -index ff5e09e207..d68bfe5cbe 100644 ---- a/sysdeps/arm/dl-machine.h -+++ b/sysdeps/arm/dl-machine.h -@@ -510,7 +510,7 @@ elf_machine_rel (struct link_map *map, const Elf32_Rel *reloc, - - case R_ARM_TLS_DTPOFF32: - if (sym != NULL) -- *reloc_addr += sym->st_value; -+ *reloc_addr = sym->st_value; - break; - - case R_ARM_TLS_TPOFF32: diff --git a/meta/recipes-core/glibc/glibc_2.34.bb b/meta/recipes-core/glibc/glibc_2.34.bb index 7efc1ec1ef..5529dc5aa3 100644 --- a/meta/recipes-core/glibc/glibc_2.34.bb +++ b/meta/recipes-core/glibc/glibc_2.34.bb @@ -37,7 +37,6 @@ SRC_URI = "${GLIBC_GIT_URI};branch=${SRCBRANCH};name=glibc \ file://0009-fsl-e500-e5500-e6500-603e-fsqrt-implementation.patch \ file://0010-ppc-sqrt-Fix-undefined-reference-to-__sqrt_finite.patch \ file://0011-__ieee754_sqrt-f-are-now-inline-functions-and-call-o.patch \ - file://0012-Quote-from-bug-1443-which-explains-what-the-patch-do.patch \ file://0013-eglibc-run-libm-err-tab.pl-with-specific-dirs-in-S.patch \ file://0014-__ieee754_sqrt-f-are-now-inline-functions-and-call-o.patch \ file://0015-sysdeps-gnu-configure.ac-handle-correctly-libc_cv_ro.patch \ -- cgit v1.2.3-54-g00ecf