[PATCH 0/3] arm64: uapi: Provide correct __BITS_PER_LONG for the compat vDSO

Thomas Weißschuh thomas.weissschuh at linutronix.de
Thu Aug 21 00:56:43 PDT 2025


The generic vDSO library uses the UAPI headers. On arm64 __BITS_PER_LONG is
always '64' even when used from the compat vDSO. In that case __GENMASK()
does an illegal bitshift, invoking undefined behaviour.

The first patch should go into the 6.17 tree.

Signed-off-by: Thomas Weißschuh <thomas.weissschuh at linutronix.de>
---
Thomas Weißschuh (3):
      arm64: uapi: Provide correct __BITS_PER_LONG for the compat vDSO
      arm64: vdso32: Stop suppressing warnings
      arm64: vdso32: Respect -Werror from kbuild

 arch/arm64/include/uapi/asm/bitsperlong.h |  5 +++++
 arch/arm64/kernel/vdso32/Makefile         | 13 +------------
 2 files changed, 6 insertions(+), 12 deletions(-)
---
base-commit: 8f5ae30d69d7543eee0d70083daf4de8fe15d585
change-id: 20250820-vdso-arm64-compat-bitsperlong-4f59ae7ef6e7

Best regards,
-- 
Thomas Weißschuh <thomas.weissschuh at linutronix.de>




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