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Date:   Fri, 13 Jan 2023 14:43:52 +0800
From:   David Gow <davidgow@...gle.com>
To:     Peter Foley <pefoley2@...oley.com>
Cc:     Richard Weinberger <richard@....at>,
        Anton Ivanov <anton.ivanov@...bridgegreys.com>,
        Johannes Berg <johannes@...solutions.net>,
        linux-um@...ts.infradead.org, linux-kernel@...r.kernel.org
Subject: Re: [PATCH 4/4] um: Use CFLAGS_vmlinux

On Fri, 13 Jan 2023 at 12:49, Peter Foley <pefoley2@...oley.com> wrote:
>
> link-vmlinux.sh doesn't use LDFLAGS_vmlinux when linking the kernel for
> UML. Move the LDFLAGS_EXESTACK options into CFLAGS_vmlinux so they're
> actually respected.
>
> e.g.
> /usr/lib/gcc/x86_64-pc-linux-gnu/12/../../../../x86_64-pc-linux-gnu/bin/ld: warning: .tmp_vmlinux.kallsyms3.o: missing .note.GNU-stack section implies executable stack
> /usr/lib/gcc/x86_64-pc-linux-gnu/12/../../../../x86_64-pc-linux-gnu/bin/ld: NOTE: This behaviour is deprecated and will be removed in a future version of the linker
> /usr/lib/gcc/x86_64-pc-linux-gnu/12/../../../../x86_64-pc-linux-gnu/bin/ld: warning: vmlinux has a LOAD segment with RWX permissions
> ---

Thanks very much for fixing this -- the LDFLAGS/CFLAGS fun here always
trips me up!

Reviewed-by: David Gow <davidgow@...gle.com>

Cheers,
-- David

>  arch/um/Makefile | 3 +--
>  1 file changed, 1 insertion(+), 2 deletions(-)
>
> diff --git a/arch/um/Makefile b/arch/um/Makefile
> index f1d4d67157be..93dfb23bd263 100644
> --- a/arch/um/Makefile
> +++ b/arch/um/Makefile
> @@ -139,11 +139,10 @@ ifeq ($(CONFIG_LD_IS_BFD),y)
>  LDFLAGS_EXECSTACK += $(call ld-option,--no-warn-rwx-segments)
>  endif
>
> -LD_FLAGS_CMDLINE = $(foreach opt,$(KBUILD_LDFLAGS),-Wl,$(opt))
> +LD_FLAGS_CMDLINE = $(foreach opt,$(KBUILD_LDFLAGS) $(LDFLAGS_EXECSTACK),-Wl,$(opt))
>
>  # Used by link-vmlinux.sh which has special support for um link
>  export CFLAGS_vmlinux := $(LINK-y) $(LINK_WRAPS) $(LD_FLAGS_CMDLINE)
> -export LDFLAGS_vmlinux := $(LDFLAGS_EXECSTACK)
>
>  # When cleaning we don't include .config, so we don't include
>  # TT or skas makefiles and don't clean skas_ptregs.h.
>
> --
> 2.39.0
>
> _______________________________________________
> linux-um mailing list
> linux-um@...ts.infradead.org
> http://lists.infradead.org/mailman/listinfo/linux-um

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