f4c74dc639
- - Add gcc7-pfe-0001-Backport-Add-entry-for-patchable_function_entry.patch gcc7-pfe-0002-Backport-Skip-fpatchable-function-entry-tests-for-nv.patch gcc7-pfe-0003-Backport-Error-out-on-nvptx-for-fpatchable-function-.patch gcc7-pfe-0004-Backport-Adapt-scan-assembler-times-for-alpha.patch gcc7-pfe-0005-Backport-patchable_function_entry-decl.c-Use-3-NOPs-.patch gcc7-pfe-0006-Backport-IBM-Z-Use-the-dedicated-NOP-instructions-fo.patch gcc7-pfe-0007-Backport-Add-regex-to-search-for-uppercase-NOP-instr.patch gcc7-pfe-0008-Backport-ICE-segmentation-fault-with-patchable_funct.patch gcc7-pfe-0009-Backport-patchable_function_entry-decl.c-Pass-mcpu-g.patch gcc7-pfe-0010-Backport-patchable_function_entry-decl.c-Do-not-run-.patch gcc7-pfe-0011-Backport-patchable_function_entry-decl.c-Add-fno-pie.patch gcc7-pfe-0012-Backport-PR-c-89946-ICE-in-assemble_start_function-a.patch gcc7-pfe-0013-Backport-targhooks.c-default_print_patchable_functio.patch gcc7-pfe-0014-Backport-Align-__patchable_function_entries-to-POINT.patch gcc7-pfe-0015-Backport-Fix-PR-93242-patchable-function-entry-broke.patch gcc7-pfe-0016-Backport-AArch64-PR92424-Fix-fpatchable-function-ent.patch gcc7-pfe-0017-Backport-Fix-patchable-function-entry-on-arc.patch gcc7-pfe-0018-Backport-Add-patch_area_size-and-patch_area_entry-to.patch gcc7-pfe-0019-Backport-testsuite-Adjust-patchable_function-tests-f.patch gcc7-pfe-0020-Backport-Use-the-section-flag-o-for-__patchable_func.patch gcc7-pfe-0021-Backport-varasm-Fix-up-__patchable_function_entries-.patch gcc7-pfe-0022-Backport-rs6000-Avoid-fpatchable-function-entry-regr.patch gcc7-pfe-0023-Fix-unwinding-issues-when-pfe-is-enabled.patch to add -fpatchable-function-entry feature to gcc-7. OBS-URL: https://build.opensuse.org/request/show/926586 OBS-URL: https://build.opensuse.org/package/show/devel:gcc/gcc7?expand=0&rev=213
89 lines
3.3 KiB
Diff
89 lines
3.3 KiB
Diff
From cd53df36c6bd6cdae12f3bb96490fdebad3eb220 Mon Sep 17 00:00:00 2001
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From: Jakub Jelinek <jakub@redhat.com>
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Date: Wed, 16 Dec 2020 16:15:35 +0100
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Subject: [PATCH 21/23] Backport varasm: Fix up __patchable_function_entries
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handling
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The SECTION_LINK_ORDER changes don't seem to work properly.
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If I compile:
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static inline __attribute__((__gnu_inline__)) __attribute__((__unused__)) __attribute__((patchable_function_entry(0, 0))) int foo (int x)
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{
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return x + 1;
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}
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static inline __attribute__((__gnu_inline__)) __attribute__((__unused__)) __attribute__((patchable_function_entry(0, 0))) int bar (int x)
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{
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return x + 2;
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}
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int
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baz (int x)
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{
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return foo (x) + 1;
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}
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int
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qux (int x)
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{
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return bar (x) + 2;
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}
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(distilled from aarch64 Linux kernel) with
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-O2 -fpatchable-function-entry=2 on aarch64 compiler configured against
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latest binutils, I get:
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...
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.section __patchable_function_entries,"awo",@progbits,baz
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...
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.section __patchable_function_entries
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...
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in the assembly, but when it is assembled, one gets:
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[ 4] __patchable_function_entries PROGBITS 0000000000000000 000060 000008 00 WAL 1 0 8
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[ 5] .rela__patchable_function_entries RELA 0000000000000000 000280 000018 18 I 12 4 8
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[ 6] __patchable_function_entries PROGBITS 0000000000000000 000068 000008 00 0 0 8
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[ 7] .rela__patchable_function_entries RELA 0000000000000000 000298 000018 18 I 12 6 8
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i.e. one writable allocated section with SHF_LINK_ORDER and another
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non-allocated non-writable without link order. In the kernel case there is
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always one entry in the WAL section and then dozens or more in the
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non-allocated one.
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The kernel then fails to link:
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WARNING: modpost: vmlinux.o (__patchable_function_entries): unexpected non-allocatable section.
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Did you forget to use "ax"/"aw" in a .S file?
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Note that for example <linux/init.h> contains
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section definitions for use in .S files.
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ld: .init.data has both ordered [`__patchable_function_entries' in init/main.o] and unordered [`.init.data' in
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+./drivers/firmware/efi/libstub/vsprintf.stub.o] sections
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ld: final link failed: bad value
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make: *** [Makefile:1175: vmlinux] Error 1
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The following patch fixes it by always forcing full section flags for
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SECTION_LINK_ORDER sections.
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2020-12-16 Jakub Jelinek <jakub@redhat.com>
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* varasm.c (default_elf_asm_named_section): Always force
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section flags even for sections with SECTION_LINK_ORDER flag.
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---
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gcc/varasm.c | 5 +++--
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1 file changed, 3 insertions(+), 2 deletions(-)
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diff --git a/gcc/varasm.c b/gcc/varasm.c
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index 7b0792ddaed..9e0e7c0976f 100644
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--- a/gcc/varasm.c
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+++ b/gcc/varasm.c
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@@ -6363,9 +6363,10 @@ default_elf_asm_named_section (const char *name, unsigned int flags,
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/* If we have already declared this section, we can use an
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abbreviated form to switch back to it -- unless this section is
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- part of a COMDAT groups, in which case GAS requires the full
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- declaration every time. */
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+ part of a COMDAT groups or with SHF_GNU_RETAIN or with SHF_LINK_ORDER,
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+ in which case GAS requires the full declaration every time. */
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if (!(HAVE_COMDAT_GROUP && (flags & SECTION_LINKONCE))
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+ && !(flags & (SECTION_RETAIN | SECTION_LINK_ORDER))
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&& (flags & SECTION_DECLARED))
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{
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fprintf (asm_out_file, "\t.section\t%s\n", name);
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--
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2.33.1
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