Re: [PATCH] riscv: ptrace: avoid BIT() in UAPI header

[Paul Walmsley]

On Mon, 30 Mar 2026, Andreas Schwab wrote:

> On Mär 30 2026, Michael Neuling wrote:
> 
> > BIT() is not available in UAPI headers — the installed linux/bits.h
> > (UAPI version) does not define it. Replace BIT() with open-coded
> > (1UL << x) which is the standard practice for UAPI headers, and drop
> > the linux/bits.h include that was added by commit 98545620b0 ("riscv:
> > ptrace: Fix BIT() compilation issues").
> 
> There is also the _BITUL macro, which may be preferable.

Thanks everyone.  Below is what I ended up with.  I'll drop Charlie's two 
patches to avoid churn.


- Paul

From: Paul Walmsley <pjw@xxxxxxxxxx>
Date: Thu, 2 Apr 2026 17:18:03 -0600
Subject: [PATCH] riscv: use _BITUL macro rather than BIT() in ptrace uapi and
 kselftests

Fix the build of non-kernel code that includes the RISC-V ptrace uapi
header, and the RISC-V validate_v_ptrace.c kselftest, by using the
_BITUL() macro rather than BIT().  BIT() is not available outside
the kernel.

Based on patches and comments from Charlie Jenkins, Michael Neuling,
and Andreas Schwab.

Fixes: 30eb191c895b ("selftests: riscv: verify ptrace rejects invalid vector csr inputs")
Fixes: 2af7c9cf021c ("riscv/ptrace: expose riscv CFI status and state via ptrace and in core files")
Cc: Andreas Schwab <schwab@xxxxxxx>
Cc: Michael Neuling <mikey@xxxxxxxxxxx>
Cc: Charlie Jenkins <thecharlesjenkins@xxxxxxxxx>
Link: https://patch.msgid.link/20260330024248.449292-1-mikey@xxxxxxxxxxx
Link: https://lore.kernel.org/linux-riscv/20260309-fix_selftests-v2-1-9d5a553a531e@xxxxxxxxx/
Link: https://lore.kernel.org/linux-riscv/20260309-fix_selftests-v2-3-9d5a553a531e@xxxxxxxxx/
Signed-off-by: Paul Walmsley <pjw@xxxxxxxxxx>
---
 arch/riscv/include/uapi/asm/ptrace.h                | 13 +++++++------
 .../selftests/riscv/vector/validate_v_ptrace.c      |  4 ++--
 2 files changed, 9 insertions(+), 8 deletions(-)

diff --git a/arch/riscv/include/uapi/asm/ptrace.h b/arch/riscv/include/uapi/asm/ptrace.h
index 18988a5f1a63..70a74adad914 100644
--- a/arch/riscv/include/uapi/asm/ptrace.h
+++ b/arch/riscv/include/uapi/asm/ptrace.h
@@ -9,6 +9,7 @@
 #ifndef __ASSEMBLER__
 
 #include <linux/types.h>
+#include <linux/const.h>
 
 #define PTRACE_GETFDPIC		33
 
@@ -138,12 +139,12 @@ struct __sc_riscv_cfi_state {
 #define PTRACE_CFI_SS_LOCK_BIT	4
 #define PTRACE_CFI_SS_PTR_BIT	5
 
-#define PTRACE_CFI_LP_EN_STATE		BIT(PTRACE_CFI_LP_EN_BIT)
-#define PTRACE_CFI_LP_LOCK_STATE	BIT(PTRACE_CFI_LP_LOCK_BIT)
-#define PTRACE_CFI_ELP_STATE		BIT(PTRACE_CFI_ELP_BIT)
-#define PTRACE_CFI_SS_EN_STATE		BIT(PTRACE_CFI_SS_EN_BIT)
-#define PTRACE_CFI_SS_LOCK_STATE	BIT(PTRACE_CFI_SS_LOCK_BIT)
-#define PTRACE_CFI_SS_PTR_STATE		BIT(PTRACE_CFI_SS_PTR_BIT)
+#define PTRACE_CFI_LP_EN_STATE		_BITUL(PTRACE_CFI_LP_EN_BIT)
+#define PTRACE_CFI_LP_LOCK_STATE	_BITUL(PTRACE_CFI_LP_LOCK_BIT)
+#define PTRACE_CFI_ELP_STATE		_BITUL(PTRACE_CFI_ELP_BIT)
+#define PTRACE_CFI_SS_EN_STATE		_BITUL(PTRACE_CFI_SS_EN_BIT)
+#define PTRACE_CFI_SS_LOCK_STATE	_BITUL(PTRACE_CFI_SS_LOCK_BIT)
+#define PTRACE_CFI_SS_PTR_STATE		_BITUL(PTRACE_CFI_SS_PTR_BIT)
 
 #define PRACE_CFI_STATE_INVALID_MASK	~(PTRACE_CFI_LP_EN_STATE | \
 					  PTRACE_CFI_LP_LOCK_STATE | \
diff --git a/tools/testing/selftests/riscv/vector/validate_v_ptrace.c b/tools/testing/selftests/riscv/vector/validate_v_ptrace.c
index 3589549f7228..7ae6fede496f 100644
--- a/tools/testing/selftests/riscv/vector/validate_v_ptrace.c
+++ b/tools/testing/selftests/riscv/vector/validate_v_ptrace.c
@@ -346,8 +346,8 @@ FIXTURE_TEARDOWN(v_csr_invalid)
 {
 }
 
-#define VECTOR_1_0		BIT(0)
-#define XTHEAD_VECTOR_0_7	BIT(1)
+#define VECTOR_1_0		_BITUL(0)
+#define XTHEAD_VECTOR_0_7	_BITUL(1)
 
 #define vector_test(x)		((x) & VECTOR_1_0)
 #define xthead_test(x)		((x) & XTHEAD_VECTOR_0_7)
-- 
2.51.0