| Message ID | 20250113155306.1922992-2-ardb+git@google.com (mailing list archive) |
|---|---|
| State | New |
| Headers | show |
| Series | [v3] kbuild: Strip runtime const RELA sections correctly | expand |
On Mon, Jan 13, 2025 at 04:53:07PM +0100, Ard Biesheuvel wrote: > From: Ard Biesheuvel <ardb@kernel.org> > > Due to the fact that runtime const ELF sections are named without a > leading period or double underscore, the RSTRIP logic that removes the > static RELA sections from vmlinux fails to identify them. This results > in a situation like below, where some sections that were supposed to get > removed are left behind. > > [Nr] Name Type Address Off Size ES Flg Lk Inf Al > > [58] runtime_shift_d_hash_shift PROGBITS ffffffff83500f50 2900f50 000014 00 A 0 0 1 > [59] .relaruntime_shift_d_hash_shift RELA 0000000000000000 55b6f00 000078 18 I 70 58 8 > [60] runtime_ptr_dentry_hashtable PROGBITS ffffffff83500f68 2900f68 000014 00 A 0 0 1 > [61] .relaruntime_ptr_dentry_hashtable RELA 0000000000000000 55b6f78 000078 18 I 70 60 8 > [62] runtime_ptr_USER_PTR_MAX PROGBITS ffffffff83500f80 2900f80 000238 00 A 0 0 1 > [63] .relaruntime_ptr_USER_PTR_MAX RELA 0000000000000000 55b6ff0 000d50 18 I 70 62 8 > > So tweak the match expression to strip all sections starting with .rel. > While at it, consolidate the logic used by RISC-V, s390 and x86 into a > single shared Makefile library command. > > Cc: Linus Torvalds <torvalds@linux-foundation.org> > Cc: Masahiro Yamada <masahiroy@kernel.org> > Cc: linux-riscv@lists.infradead.org > Cc: linux-s390@vger.kernel.org > Cc: Ron Economos <re@w6rz.net> > Link: https://lore.kernel.org/all/CAHk-=wjk3ynjomNvFN8jf9A1k=qSc=JFF591W00uXj-qqNUxPQ@mail.gmail.com/ > Signed-off-by: Ard Biesheuvel <ardb@kernel.org> > --- > v3: put back missing 'endif' to fix the RISC-V build > v2: add missing include of scripts/Makefile.lib > > arch/riscv/Makefile.postlink | 8 ++------ > arch/s390/Makefile.postlink | 6 +----- > arch/x86/Makefile.postlink | 6 +----- > scripts/Makefile.lib | 3 +++ > 4 files changed, 7 insertions(+), 18 deletions(-) > > diff --git a/arch/riscv/Makefile.postlink b/arch/riscv/Makefile.postlink > index 829b9abc91f6..750d2784f69e 100644 > --- a/arch/riscv/Makefile.postlink > +++ b/arch/riscv/Makefile.postlink When I compile x86 as relocatable I see the problem that you are fixing here, but I don't see it on riscv. It's probably better to keep around this code for riscv, but I don't think it even needs this stripping? I am adding Alex since he added this for riscv. Anyways this works as expected: Reviewed-by: Charlie Jenkins <charlie@rivosinc.com> Tested-by: Charlie Jenkins <charlie@rivosinc.com> > @@ -10,6 +10,7 @@ __archpost: > > -include include/config/auto.conf > include $(srctree)/scripts/Kbuild.include > +include $(srctree)/scripts/Makefile.lib > > quiet_cmd_relocs_check = CHKREL $@ > cmd_relocs_check = \ > @@ -19,11 +20,6 @@ ifdef CONFIG_RELOCATABLE > quiet_cmd_cp_vmlinux_relocs = CPREL vmlinux.relocs > cmd_cp_vmlinux_relocs = cp vmlinux vmlinux.relocs > > -quiet_cmd_relocs_strip = STRIPREL $@ > -cmd_relocs_strip = $(OBJCOPY) --remove-section='.rel.*' \ > - --remove-section='.rel__*' \ > - --remove-section='.rela.*' \ > - --remove-section='.rela__*' $@ > endif > > # `@true` prevents complaint when there is nothing to be done > @@ -33,7 +27,7 @@ vmlinux: FORCE > ifdef CONFIG_RELOCATABLE > $(call if_changed,relocs_check) > $(call if_changed,cp_vmlinux_relocs) > - $(call if_changed,relocs_strip) > + $(call if_changed,strip_relocs) > endif > > clean: > diff --git a/arch/s390/Makefile.postlink b/arch/s390/Makefile.postlink > index df82f5410769..1ae5478cd6ac 100644 > --- a/arch/s390/Makefile.postlink > +++ b/arch/s390/Makefile.postlink > @@ -11,6 +11,7 @@ __archpost: > > -include include/config/auto.conf > include $(srctree)/scripts/Kbuild.include > +include $(srctree)/scripts/Makefile.lib > > CMD_RELOCS=arch/s390/tools/relocs > OUT_RELOCS = arch/s390/boot > @@ -19,11 +20,6 @@ quiet_cmd_relocs = RELOCS $(OUT_RELOCS)/relocs.S > mkdir -p $(OUT_RELOCS); \ > $(CMD_RELOCS) $@ > $(OUT_RELOCS)/relocs.S > > -quiet_cmd_strip_relocs = RSTRIP $@ > - cmd_strip_relocs = \ > - $(OBJCOPY) --remove-section='.rel.*' --remove-section='.rel__*' \ > - --remove-section='.rela.*' --remove-section='.rela__*' $@ > - > vmlinux: FORCE > $(call cmd,relocs) > $(call cmd,strip_relocs) > diff --git a/arch/x86/Makefile.postlink b/arch/x86/Makefile.postlink > index fef2e977cc7d..8b8a68162c94 100644 > --- a/arch/x86/Makefile.postlink > +++ b/arch/x86/Makefile.postlink > @@ -11,6 +11,7 @@ __archpost: > > -include include/config/auto.conf > include $(srctree)/scripts/Kbuild.include > +include $(srctree)/scripts/Makefile.lib > > CMD_RELOCS = arch/x86/tools/relocs > OUT_RELOCS = arch/x86/boot/compressed > @@ -20,11 +21,6 @@ quiet_cmd_relocs = RELOCS $(OUT_RELOCS)/$@.relocs > $(CMD_RELOCS) $@ > $(OUT_RELOCS)/$@.relocs; \ > $(CMD_RELOCS) --abs-relocs $@ > > -quiet_cmd_strip_relocs = RSTRIP $@ > - cmd_strip_relocs = \ > - $(OBJCOPY) --remove-section='.rel.*' --remove-section='.rel__*' \ > - --remove-section='.rela.*' --remove-section='.rela__*' $@ > - > # `@true` prevents complaint when there is nothing to be done > > vmlinux: FORCE > diff --git a/scripts/Makefile.lib b/scripts/Makefile.lib > index 7395200538da..f604f51d23ca 100644 > --- a/scripts/Makefile.lib > +++ b/scripts/Makefile.lib > @@ -374,6 +374,9 @@ quiet_cmd_ar = AR $@ > quiet_cmd_objcopy = OBJCOPY $@ > cmd_objcopy = $(OBJCOPY) $(OBJCOPYFLAGS) $(OBJCOPYFLAGS_$(@F)) $< $@ > > +quiet_cmd_strip_relocs = RSTRIP $@ > +cmd_strip_relocs = $(OBJCOPY) --remove-section='.rel*' $@ > + > # Gzip > # --------------------------------------------------------------------------- > > -- > 2.47.1.688.g23fc6f90ad-goog > > > _______________________________________________ > linux-riscv mailing list > linux-riscv@lists.infradead.org > http://lists.infradead.org/mailman/listinfo/linux-riscv
On Thu, 16 Jan 2025 at 23:02, Charlie Jenkins <charlie@rivosinc.com> wrote: > > On Mon, Jan 13, 2025 at 04:53:07PM +0100, Ard Biesheuvel wrote: > > From: Ard Biesheuvel <ardb@kernel.org> > > > > Due to the fact that runtime const ELF sections are named without a > > leading period or double underscore, the RSTRIP logic that removes the > > static RELA sections from vmlinux fails to identify them. This results > > in a situation like below, where some sections that were supposed to get > > removed are left behind. > > > > [Nr] Name Type Address Off Size ES Flg Lk Inf Al > > > > [58] runtime_shift_d_hash_shift PROGBITS ffffffff83500f50 2900f50 000014 00 A 0 0 1 > > [59] .relaruntime_shift_d_hash_shift RELA 0000000000000000 55b6f00 000078 18 I 70 58 8 > > [60] runtime_ptr_dentry_hashtable PROGBITS ffffffff83500f68 2900f68 000014 00 A 0 0 1 > > [61] .relaruntime_ptr_dentry_hashtable RELA 0000000000000000 55b6f78 000078 18 I 70 60 8 > > [62] runtime_ptr_USER_PTR_MAX PROGBITS ffffffff83500f80 2900f80 000238 00 A 0 0 1 > > [63] .relaruntime_ptr_USER_PTR_MAX RELA 0000000000000000 55b6ff0 000d50 18 I 70 62 8 > > > > So tweak the match expression to strip all sections starting with .rel. > > While at it, consolidate the logic used by RISC-V, s390 and x86 into a > > single shared Makefile library command. > > > > Cc: Linus Torvalds <torvalds@linux-foundation.org> > > Cc: Masahiro Yamada <masahiroy@kernel.org> > > Cc: linux-riscv@lists.infradead.org > > Cc: linux-s390@vger.kernel.org > > Cc: Ron Economos <re@w6rz.net> > > Link: https://lore.kernel.org/all/CAHk-=wjk3ynjomNvFN8jf9A1k=qSc=JFF591W00uXj-qqNUxPQ@mail.gmail.com/ > > Signed-off-by: Ard Biesheuvel <ardb@kernel.org> > > --- > > v3: put back missing 'endif' to fix the RISC-V build > > v2: add missing include of scripts/Makefile.lib > > > > arch/riscv/Makefile.postlink | 8 ++------ > > arch/s390/Makefile.postlink | 6 +----- > > arch/x86/Makefile.postlink | 6 +----- > > scripts/Makefile.lib | 3 +++ > > 4 files changed, 7 insertions(+), 18 deletions(-) > > > > diff --git a/arch/riscv/Makefile.postlink b/arch/riscv/Makefile.postlink > > index 829b9abc91f6..750d2784f69e 100644 > > --- a/arch/riscv/Makefile.postlink > > +++ b/arch/riscv/Makefile.postlink > > When I compile x86 as relocatable I see the problem that you are fixing > here, but I don't see it on riscv. That is because riscv does not yet support optimized runtime constants. Only arm64, s390 and x86 implement this today but I'd expect other architectures to follow suit. > It's probably better to keep around > this code for riscv, but I don't think it even needs this stripping? I > am adding Alex since he added this for riscv. > If vmlinux is linked with --emit-relocs, the stripping is probably necessary, or you get a lot of metadata in vmlinux that is not needed for debugging. > Anyways this works as expected: > > Reviewed-by: Charlie Jenkins <charlie@rivosinc.com> > Tested-by: Charlie Jenkins <charlie@rivosinc.com> > Thanks.
diff --git a/arch/riscv/Makefile.postlink b/arch/riscv/Makefile.postlink index 829b9abc91f6..750d2784f69e 100644 --- a/arch/riscv/Makefile.postlink +++ b/arch/riscv/Makefile.postlink @@ -10,6 +10,7 @@ __archpost: -include include/config/auto.conf include $(srctree)/scripts/Kbuild.include +include $(srctree)/scripts/Makefile.lib quiet_cmd_relocs_check = CHKREL $@ cmd_relocs_check = \ @@ -19,11 +20,6 @@ ifdef CONFIG_RELOCATABLE quiet_cmd_cp_vmlinux_relocs = CPREL vmlinux.relocs cmd_cp_vmlinux_relocs = cp vmlinux vmlinux.relocs -quiet_cmd_relocs_strip = STRIPREL $@ -cmd_relocs_strip = $(OBJCOPY) --remove-section='.rel.*' \ - --remove-section='.rel__*' \ - --remove-section='.rela.*' \ - --remove-section='.rela__*' $@ endif # `@true` prevents complaint when there is nothing to be done @@ -33,7 +27,7 @@ vmlinux: FORCE ifdef CONFIG_RELOCATABLE $(call if_changed,relocs_check) $(call if_changed,cp_vmlinux_relocs) - $(call if_changed,relocs_strip) + $(call if_changed,strip_relocs) endif clean: diff --git a/arch/s390/Makefile.postlink b/arch/s390/Makefile.postlink index df82f5410769..1ae5478cd6ac 100644 --- a/arch/s390/Makefile.postlink +++ b/arch/s390/Makefile.postlink @@ -11,6 +11,7 @@ __archpost: -include include/config/auto.conf include $(srctree)/scripts/Kbuild.include +include $(srctree)/scripts/Makefile.lib CMD_RELOCS=arch/s390/tools/relocs OUT_RELOCS = arch/s390/boot @@ -19,11 +20,6 @@ quiet_cmd_relocs = RELOCS $(OUT_RELOCS)/relocs.S mkdir -p $(OUT_RELOCS); \ $(CMD_RELOCS) $@ > $(OUT_RELOCS)/relocs.S -quiet_cmd_strip_relocs = RSTRIP $@ - cmd_strip_relocs = \ - $(OBJCOPY) --remove-section='.rel.*' --remove-section='.rel__*' \ - --remove-section='.rela.*' --remove-section='.rela__*' $@ - vmlinux: FORCE $(call cmd,relocs) $(call cmd,strip_relocs) diff --git a/arch/x86/Makefile.postlink b/arch/x86/Makefile.postlink index fef2e977cc7d..8b8a68162c94 100644 --- a/arch/x86/Makefile.postlink +++ b/arch/x86/Makefile.postlink @@ -11,6 +11,7 @@ __archpost: -include include/config/auto.conf include $(srctree)/scripts/Kbuild.include +include $(srctree)/scripts/Makefile.lib CMD_RELOCS = arch/x86/tools/relocs OUT_RELOCS = arch/x86/boot/compressed @@ -20,11 +21,6 @@ quiet_cmd_relocs = RELOCS $(OUT_RELOCS)/$@.relocs $(CMD_RELOCS) $@ > $(OUT_RELOCS)/$@.relocs; \ $(CMD_RELOCS) --abs-relocs $@ -quiet_cmd_strip_relocs = RSTRIP $@ - cmd_strip_relocs = \ - $(OBJCOPY) --remove-section='.rel.*' --remove-section='.rel__*' \ - --remove-section='.rela.*' --remove-section='.rela__*' $@ - # `@true` prevents complaint when there is nothing to be done vmlinux: FORCE diff --git a/scripts/Makefile.lib b/scripts/Makefile.lib index 7395200538da..f604f51d23ca 100644 --- a/scripts/Makefile.lib +++ b/scripts/Makefile.lib @@ -374,6 +374,9 @@ quiet_cmd_ar = AR $@ quiet_cmd_objcopy = OBJCOPY $@ cmd_objcopy = $(OBJCOPY) $(OBJCOPYFLAGS) $(OBJCOPYFLAGS_$(@F)) $< $@ +quiet_cmd_strip_relocs = RSTRIP $@ +cmd_strip_relocs = $(OBJCOPY) --remove-section='.rel*' $@ + # Gzip # ---------------------------------------------------------------------------