Re: linux-next: build failure after merge of the mm-nonmm-unstable tree

[Sasha Levin <sashal@kernel.org>]

On Sun, Dec 21, 2025 at 01:58:17PM +1100, Finn Thain wrote:
>
>On Thu, 18 Dec 2025, Stephen Rothwell wrote:
>
>> After merging the mm-nonmm-unstable tree, today's linux-next build
>> (x86_64 allmodconfig) failed like this:
>>
>> x86_64-linux-gnu-ld: error: unplaced orphan section `__bug_table' from `arch/x86/boot/compressed/sev-handle-vc.o'
>>
>
>I found that I could reproduce the same build failure after applying
>Peter's patch to v6.19-rc1. So it's not confined to linux-next. I used
>allnoconfig with CONFIG_LD_ORPHAN_WARN_LEVEL=error and
>CONFIG_AMD_MEM_ENCRYPT=y because allmodconfig takes forever to build.
>
>The patch in question is this one:
>https://lore.kernel.org/lkml/0c18fd08ef19497768070783da28086e01d11a00.1765866665.git.fthain@linux-m68k.org/
>
>I may have found a solution for the problem, but I don't understand this
>code, so I've Cc'd Ard et al. I don't know whether the __bug_table section
>is relevant to sev-handle-vc.c. If that section is not desired, I propose
>to make this change to Peter's patch --

I think that the issue here is that we're trying to use WARN in the early boot
context. We should probably add CONFIG_DEBUG_ATOMIC to the list of configs we
disable for that:

diff --git a/arch/x86/boot/compressed/misc.h b/arch/x86/boot/compressed/misc.h
index 4f86c5903e03..bb36dcef7d08 100644
--- a/arch/x86/boot/compressed/misc.h
+++ b/arch/x86/boot/compressed/misc.h
@@ -14,6 +14,7 @@
  #undef CONFIG_ARCH_HAS_LAZY_MMU_MODE
  #undef CONFIG_KASAN
  #undef CONFIG_KASAN_GENERIC
+#undef CONFIG_DEBUG_ATOMIC

-- 
Thanks,
Sasha