On Sun, 15 May 2022 11:05:23 +0100 Catalin Marinas catalin.marinas@arm.com wrote:
Hi,
On Wed, May 11, 2022 at 06:21:29PM +0100, Andre Przywara wrote:
The "bti" selftests are built with -nostdlib, which apparently automatically creates a statically linked binary, which is what we want and need for BTI (to avoid interactions with the dynamic linker).
However this is not true when building a PIE binary, which some toolchains (Ubuntu) configure as the default. When compiling btitest with such a toolchain, it will create a dynamically linked binary, which will probably fail some tests, as the dynamic linker might not support BTI: =================== TAP version 13 1..18 not ok 1 nohint_func/call_using_br_x0 not ok 2 nohint_func/call_using_br_x16 not ok 3 nohint_func/call_using_blr .... ===================
To make sure we create static binaries, add an explicit -static on the linker command line. This forces static linking even if the toolchain defaults to PIE builds, and fixes btitest runs on BTI enabled machines.
Signed-off-by: Andre Przywara andre.przywara@arm.com
Does this need to go in as a fix (cc stable, fixes tag)?
I dimly remember some discussion about stable fixes not being a real thing for the selftests? In any case:
Fixes: 314bcbf09f14 ("kselftest: arm64: Add BTI tests")
Cheers, Andre