[PATCH 4/6] prctl: rename branch landing pad implementation functions to be more explicit
From: Paul Walmsley
Date: Fri Apr 03 2026 - 21:43:05 EST
Per Linus' comments about the unreadability of abbreviations such as
"indir_br_lp", rename the three prctl() implementation functions to be more
explicit. This involves renaming "indir_br_lp_status" in the function
names to "branch_landing_pad_state".
While here, add _prctl_ into the function names, following the
speculation control prctl implementation functions.
Link: https://lore.kernel.org/linux-riscv/CAHk-=whhSLGZAx3N5jJpb4GLFDqH_QvS07D+6BnkPWmCEzTAgw@xxxxxxxxxxxxxx/
Cc: Deepak Gupta <debug@xxxxxxxxxxxx>
Cc: Linus Torvalds <torvalds@xxxxxxxxxxxxxxxxxxxx>
Cc: Mark Brown <broonie@xxxxxxxxxx>
Signed-off-by: Paul Walmsley <pjw@xxxxxxxxxx>
---
arch/riscv/kernel/usercfi.c | 16 ++++++++--------
include/linux/cpu.h | 6 +++---
kernel/sys.c | 15 ++++++++-------
3 files changed, 19 insertions(+), 18 deletions(-)
diff --git a/arch/riscv/kernel/usercfi.c b/arch/riscv/kernel/usercfi.c
index 9052171c1a8c..04ab1eb8df29 100644
--- a/arch/riscv/kernel/usercfi.c
+++ b/arch/riscv/kernel/usercfi.c
@@ -457,7 +457,8 @@ int arch_lock_shadow_stack_status(struct task_struct *task,
return 0;
}
-int arch_get_indir_br_lp_status(struct task_struct *t, unsigned long __user *status)
+int arch_prctl_get_branch_landing_pad_state(struct task_struct *t,
+ unsigned long __user *state)
{
unsigned long fcfi_status = 0;
@@ -467,10 +468,10 @@ int arch_get_indir_br_lp_status(struct task_struct *t, unsigned long __user *sta
/* indirect branch tracking is enabled on the task or not */
fcfi_status |= (is_indir_lp_enabled(t) ? PR_INDIR_BR_LP_ENABLE : 0);
- return copy_to_user(status, &fcfi_status, sizeof(fcfi_status)) ? -EFAULT : 0;
+ return copy_to_user(state, &fcfi_status, sizeof(fcfi_status)) ? -EFAULT : 0;
}
-int arch_set_indir_br_lp_status(struct task_struct *t, unsigned long status)
+int arch_prctl_set_branch_landing_pad_state(struct task_struct *t, unsigned long state)
{
bool enable_indir_lp = false;
@@ -482,24 +483,23 @@ int arch_set_indir_br_lp_status(struct task_struct *t, unsigned long status)
return -EINVAL;
/* Reject unknown flags */
- if (status & ~PR_INDIR_BR_LP_ENABLE)
+ if (state & ~PR_INDIR_BR_LP_ENABLE)
return -EINVAL;
- enable_indir_lp = (status & PR_INDIR_BR_LP_ENABLE);
+ enable_indir_lp = (state & PR_INDIR_BR_LP_ENABLE);
set_indir_lp_status(t, enable_indir_lp);
return 0;
}
-int arch_lock_indir_br_lp_status(struct task_struct *task,
- unsigned long arg)
+int arch_prctl_lock_branch_landing_pad_state(struct task_struct *task)
{
/*
* If indirect branch tracking is not supported or not enabled on task,
* nothing to lock here
*/
if (!is_user_lpad_enabled() ||
- !is_indir_lp_enabled(task) || arg != 0)
+ !is_indir_lp_enabled(task))
return -EINVAL;
set_indir_lp_lock(task, true);
diff --git a/include/linux/cpu.h b/include/linux/cpu.h
index 8239cd95a005..9b6b0d87fdb0 100644
--- a/include/linux/cpu.h
+++ b/include/linux/cpu.h
@@ -229,8 +229,8 @@ static inline bool cpu_attack_vector_mitigated(enum cpu_attack_vectors v)
#define smt_mitigations SMT_MITIGATIONS_OFF
#endif
-int arch_get_indir_br_lp_status(struct task_struct *t, unsigned long __user *status);
-int arch_set_indir_br_lp_status(struct task_struct *t, unsigned long status);
-int arch_lock_indir_br_lp_status(struct task_struct *t, unsigned long status);
+int arch_prctl_get_branch_landing_pad_state(struct task_struct *t, unsigned long __user *state);
+int arch_prctl_set_branch_landing_pad_state(struct task_struct *t, unsigned long state);
+int arch_prctl_lock_branch_landing_pad_state(struct task_struct *t);
#endif /* _LINUX_CPU_H_ */
diff --git a/kernel/sys.c b/kernel/sys.c
index c86eba9aa7e9..a5e0c187bbbf 100644
--- a/kernel/sys.c
+++ b/kernel/sys.c
@@ -2388,17 +2388,18 @@ int __weak arch_lock_shadow_stack_status(struct task_struct *t, unsigned long st
return -EINVAL;
}
-int __weak arch_get_indir_br_lp_status(struct task_struct *t, unsigned long __user *status)
+int __weak arch_prctl_get_branch_landing_pad_state(struct task_struct *t,
+ unsigned long __user *state)
{
return -EINVAL;
}
-int __weak arch_set_indir_br_lp_status(struct task_struct *t, unsigned long status)
+int __weak arch_prctl_set_branch_landing_pad_state(struct task_struct *t, unsigned long state)
{
return -EINVAL;
}
-int __weak arch_lock_indir_br_lp_status(struct task_struct *t, unsigned long status)
+int __weak arch_prctl_lock_branch_landing_pad_state(struct task_struct *t)
{
return -EINVAL;
}
@@ -2891,17 +2892,17 @@ SYSCALL_DEFINE5(prctl, int, option, unsigned long, arg2, unsigned long, arg3,
case PR_GET_INDIR_BR_LP_STATUS:
if (arg3 || arg4 || arg5)
return -EINVAL;
- error = arch_get_indir_br_lp_status(me, (unsigned long __user *)arg2);
+ error = arch_prctl_get_branch_landing_pad_state(me, (unsigned long __user *)arg2);
break;
case PR_SET_INDIR_BR_LP_STATUS:
if (arg3 || arg4 || arg5)
return -EINVAL;
- error = arch_set_indir_br_lp_status(me, arg2);
+ error = arch_prctl_set_branch_landing_pad_state(me, arg2);
break;
case PR_LOCK_INDIR_BR_LP_STATUS:
- if (arg3 || arg4 || arg5)
+ if (arg2 || arg3 || arg4 || arg5)
return -EINVAL;
- error = arch_lock_indir_br_lp_status(me, arg2);
+ error = arch_prctl_lock_branch_landing_pad_state(me);
break;
default:
trace_task_prctl_unknown(option, arg2, arg3, arg4, arg5);