Merge tag 'ffs-const-v6.18-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/kees/linux

Pull ffs const-attribute cleanups from Kees Cook:
 "While working on various hardening refactoring a while back we
  encountered inconsistencies in the application of __attribute_const__
  on the ffs() family of functions.

  This series fixes this across all archs and adds KUnit tests.

  Notably, this found a theoretical underflow in PCI (also fixed here)
  and uncovered an inefficiency in ARC (fixed in the ARC arch PR). I
  kept the series separate from the general hardening PR since it is a
  stand-alone "topic".

   - PCI: Fix theoretical underflow in use of ffs().

   - Universally apply __attribute_const__ to all architecture's
     ffs()-family of functions.

   - Add KUnit tests for ffs() behavior and const-ness"

* tag 'ffs-const-v6.18-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/kees/linux:
  KUnit: ffs: Validate all the __attribute_const__ annotations
  sparc: Add __attribute_const__ to ffs()-family implementations
  xtensa: Add __attribute_const__ to ffs()-family implementations
  s390: Add __attribute_const__ to ffs()-family implementations
  parisc: Add __attribute_const__ to ffs()-family implementations
  mips: Add __attribute_const__ to ffs()-family implementations
  m68k: Add __attribute_const__ to ffs()-family implementations
  openrisc: Add __attribute_const__ to ffs()-family implementations
  riscv: Add __attribute_const__ to ffs()-family implementations
  hexagon: Add __attribute_const__ to ffs()-family implementations
  alpha: Add __attribute_const__ to ffs()-family implementations
  sh: Add __attribute_const__ to ffs()-family implementations
  powerpc: Add __attribute_const__ to ffs()-family implementations
  x86: Add __attribute_const__ to ffs()-family implementations
  csky: Add __attribute_const__ to ffs()-family implementations
  bitops: Add __attribute_const__ to generic ffs()-family implementations
  KUnit: Introduce ffs()-family tests
  PCI: Test for bit underflow in pcie_set_readrq()

4 files changed, 4 insertions, 4 deletions

diff --git a/arch/openrisc/include/asm/bitops/__ffs.h b/arch/openrisc/include/asm/bitops/__ffs.h
index 1e224b616fdf..4827b66530b2 100644
--- a/arch/openrisc/include/asm/bitops/__ffs.h
+++ b/arch/openrisc/include/asm/bitops/__ffs.h
@@ -11,7 +11,7 @@
 
 #ifdef CONFIG_OPENRISC_HAVE_INST_FF1
 
-static inline unsigned long __ffs(unsigned long x)
+static inline __attribute_const__ unsigned long __ffs(unsigned long x)
 {
 	int ret;
 
diff --git a/arch/openrisc/include/asm/bitops/__fls.h b/arch/openrisc/include/asm/bitops/__fls.h
index 9658446ad141..637cc76fe4b7 100644
--- a/arch/openrisc/include/asm/bitops/__fls.h
+++ b/arch/openrisc/include/asm/bitops/__fls.h
@@ -11,7 +11,7 @@
 
 #ifdef CONFIG_OPENRISC_HAVE_INST_FL1
 
-static inline unsigned long __fls(unsigned long x)
+static inline __attribute_const__ unsigned long __fls(unsigned long x)
 {
 	int ret;
 
diff --git a/arch/openrisc/include/asm/bitops/ffs.h b/arch/openrisc/include/asm/bitops/ffs.h
index b4c835d6bc84..536a60ab9cc3 100644
--- a/arch/openrisc/include/asm/bitops/ffs.h
+++ b/arch/openrisc/include/asm/bitops/ffs.h
@@ -10,7 +10,7 @@
 
 #ifdef CONFIG_OPENRISC_HAVE_INST_FF1
 
-static inline int ffs(int x)
+static inline __attribute_const__ int ffs(int x)
 {
 	int ret;
 
diff --git a/arch/openrisc/include/asm/bitops/fls.h b/arch/openrisc/include/asm/bitops/fls.h
index 6b77f6556fb9..77da7639bb3e 100644
--- a/arch/openrisc/include/asm/bitops/fls.h
+++ b/arch/openrisc/include/asm/bitops/fls.h
@@ -11,7 +11,7 @@
 
 #ifdef CONFIG_OPENRISC_HAVE_INST_FL1
 
-static inline int fls(unsigned int x)
+static inline __attribute_const__ int fls(unsigned int x)
 {
 	int ret;