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* [PATCH] powerpc/vmlinux.lds: Drop .interp description
@ 2025-10-18 17:52 Nathan Chancellor
  2025-10-21  8:18 ` Vishal Chourasia
  2025-11-21  2:53 ` Madhavan Srinivasan
  0 siblings, 2 replies; 5+ messages in thread
From: Nathan Chancellor @ 2025-10-18 17:52 UTC (permalink / raw)
  To: Madhavan Srinivasan, Michael Ellerman, Nicholas Piggin,
	Christophe Leroy
  Cc: Nick Desaulniers, Bill Wendling, Justin Stitt, linuxppc-dev,
	linux-kernel, llvm, Vishal Chourasia, Nathan Chancellor

Commit da30705c4621 ("arch/powerpc: Remove .interp section in vmlinux")
intended to drop the .interp section from vmlinux but even with this
change, relocatable kernels linked with ld.lld contain an empty .interp
section, which ends up causing crashes in GDB [1].

  $ make -skj"$(nproc)" ARCH=powerpc LLVM=1 clean pseries_le_defconfig vmlinux

  $ llvm-readelf -S vmlinux | grep interp
    [44] .interp           PROGBITS        c0000000021ddb34 21edb34 000000 00   A  0   0  1

There appears to be a subtle difference between GNU ld and ld.lld when
it comes to discarding sections that specify load addresses [2].

Since '--no-dynamic-linker' prevents emission of the .interp section,
there is no need to describe it in the output sections of the vmlinux
linker script. Drop the .interp section description from vmlinux.lds.S
to avoid this issue altogether.

Link: https://sourceware.org/bugzilla/show_bug.cgi?id=33481 [1]
Link: https://github.com/ClangBuiltLinux/linux/issues/2137 [2]
Reported-by: Vishal Chourasia <vishalc@linux.ibm.com>
Closes: https://lore.kernel.org/20251013040148.560439-1-vishalc@linux.ibm.com/
Signed-off-by: Nathan Chancellor <nathan@kernel.org>
---
 arch/powerpc/kernel/vmlinux.lds.S | 1 -
 1 file changed, 1 deletion(-)

diff --git a/arch/powerpc/kernel/vmlinux.lds.S b/arch/powerpc/kernel/vmlinux.lds.S
index de6ee7d35cff..15850296c0a9 100644
--- a/arch/powerpc/kernel/vmlinux.lds.S
+++ b/arch/powerpc/kernel/vmlinux.lds.S
@@ -330,7 +330,6 @@ SECTIONS
 	}
 	.hash : AT(ADDR(.hash) - LOAD_OFFSET) { *(.hash) }
 	.gnu.hash : AT(ADDR(.gnu.hash) - LOAD_OFFSET) { *(.gnu.hash) }
-	.interp : AT(ADDR(.interp) - LOAD_OFFSET) { *(.interp) }
 	.rela.dyn : AT(ADDR(.rela.dyn) - LOAD_OFFSET)
 	{
 		__rela_dyn_start = .;

---
base-commit: 3a8660878839faadb4f1a6dd72c3179c1df56787
change-id: 20251018-ppc-fix-lld-interp-1a78c361cd42

Best regards,
--  
Nathan Chancellor <nathan@kernel.org>


^ permalink raw reply related	[flat|nested] 5+ messages in thread

end of thread, other threads:[~2025-11-21  4:44 UTC | newest]

Thread overview: 5+ messages (download: mbox.gz follow: Atom feed
-- links below jump to the message on this page --
2025-10-18 17:52 [PATCH] powerpc/vmlinux.lds: Drop .interp description Nathan Chancellor
2025-10-21  8:18 ` Vishal Chourasia
2025-10-27  7:46   ` Vishal Chourasia
2025-10-28  8:58     ` Madhavan Srinivasan
2025-11-21  2:53 ` Madhavan Srinivasan

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