[Buildroot] [PATCH] linux: disable SSP support when needed

[Julien Olivain]

On 27/08/2026 23:21, Romain Naour via buildroot wrote:
> x86 and x86_64 kernels >= 6.15 now requires ssp toolchain support
> when CONFIG_STACKPROTECTOR is enabled [1].
> 
> For toolchains without SSP support, make sure to disable
> CONFIG_STACKPROTECTOR to avoid link issues when building kernel
> modules.
> 
>   MODPOST Module.symvers
>   ERROR: modpost: "__stack_chk_guard" [drivers/<module>.ko] undefined!
> 
> While the SSP support is mandatory for glibc and musl based toolchains
> [2], it's still optional for uClibc-ng based toolchains and not enabled
> by default when building a new toolchain.
> 
> The Toolchain builder project enabled recently the SSP support for all
> uClibc toolchains [3] to avoid such issue.
> 
> But x86 (32bits) musl based toolchains lack of SSP support due to a
> long term gcc issue [4]. For a decade Alpine Linux, OpenWRT and Yocto
> povide additional gcc and musl patches to workaround the gcc issue [5]
> 
> We may consider in the long term removing the support for toolchains
> without SSP and doing so removing x86 (32bits) musl toolchain.
> 
> Fixes:
> https://gitlab.com/buildroot.org/toolchains-builder/-/jobs/15832356731 
> (x86-64--uclibc--bleeding-edge_test)
> https://gitlab.com/buildroot.org/toolchains-builder/-/jobs/15832356104 
> (x86-64--uclibc--stable_test)
> 
> https://gitlab.com/buildroot.org/toolchains-builder/-/jobs/15832355429 
> (x86-64-core-i7--uclibc--bleeding-edge_test)
> https://gitlab.com/buildroot.org/toolchains-builder/-/jobs/15832354341 
> (x86-64-core-i7--uclibc--stable_test)
> 
> https://gitlab.com/buildroot.org/toolchains-builder/-/jobs/15832326525 
> (x86-64-v2--uclibc--bleeding-edge_test)
> https://gitlab.com/buildroot.org/toolchains-builder/-/jobs/15832316220 
> (x86-64-v2--uclibc--stable_test)
> 
> https://gitlab.com/buildroot.org/toolchains-builder/-/jobs/15819139512 
> (x86-i686--uclibc--stable_test)
> https://gitlab.com/buildroot.org/toolchains-builder/-/jobs/15819139511 
> (x86-i686--uclibc--bleeding-edge_test)
> 
> https://gitlab.com/buildroot.org/toolchains-builder/-/jobs/15819139510 
> (x86-i686--musl--stable_test)
> https://gitlab.com/buildroot.org/toolchains-builder/-/jobs/15819139509 
> (x86-i686--musl--bleeding-edge_test)
> 
> https://gitlab.com/buildroot.org/toolchains-builder/-/jobs/15819139506 
> (x86-core2--uclibc--stable_test)
> https://gitlab.com/buildroot.org/toolchains-builder/-/jobs/15819139505 
> (x86-core2--uclibc--bleeding-edge_test)
> 
> https://gitlab.com/buildroot.org/toolchains-builder/-/jobs/15819139504 
> (x86-core2--musl--stable_test)
> https://gitlab.com/buildroot.org/toolchains-builder/-/jobs/15819139503 
> (x86-core2--musl--bleeding-edge_test)
> 
> [1] 
> https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git/commit/?id=0ee2689b9374d6fd5f43b703713a53227
> [2] e811f5154944147e4fceb8d199321aba91070587
> [3] 
> https://gitlab.com/buildroot.org/toolchains-builder/-/commit/90413f665735e1786cca2403cd1ff997920c99ae
> [4] https://www.openwall.com/lists/musl/2016/12/04/2
> [5] https://git.alpinelinux.org/aports/tree/main/musl/APKBUILD#n65
>     
> https://git.alpinelinux.org/aports/tree/main/gcc/0018-Alpine-musl-package-provides-libssp_nonshared.a.-We-.patch
>     
> https://github.com/openwrt/openwrt/blob/v25.12.5/toolchain/gcc/patches-15.x/230-musl_libssp.patch
>     
> https://github.com/openwrt/openwrt/blob/v25.12.5/toolchain/musl/patches/200-add_libssp_nonshared.patch
>     
> https://github.com/openembedded/openembedded-core/commit/77fb841f2e747dc7fb5e9234d870a7a32a74d09b
> 
> Cc: Thomas Petazzoni <thomas.petazzoni at bootlin.com>
> Signed-off-by: Romain Naour <romain.naour at smile.fr>

Applied to master, thanks.