[PATCH] riscv: make runtime const not usable by modules

Jisheng Zhang posted 1 patch 1 month, 3 weeks ago
arch/riscv/include/asm/runtime-const.h | 4 ++++
1 file changed, 4 insertions(+)
[PATCH] riscv: make runtime const not usable by modules
Posted by Jisheng Zhang 1 month, 3 weeks ago
Similar as commit 284922f4c563 ("x86: uaccess: don't use runtime-const
rewriting in modules") does, make riscv's runtime const not usable by
modules too, to "make sure this doesn't get forgotten the next time
somebody wants to do runtime constant optimizations". The reason is
well explained in the above commit: "The runtime-const infrastructure
was never designed to handle the modular case, because the constant
fixup is only done at boot time for core kernel code."

Signed-off-by: Jisheng Zhang <jszhang@kernel.org>
---
 arch/riscv/include/asm/runtime-const.h | 4 ++++
 1 file changed, 4 insertions(+)

diff --git a/arch/riscv/include/asm/runtime-const.h b/arch/riscv/include/asm/runtime-const.h
index d766e2b9e6df..900db0a103d0 100644
--- a/arch/riscv/include/asm/runtime-const.h
+++ b/arch/riscv/include/asm/runtime-const.h
@@ -2,6 +2,10 @@
 #ifndef _ASM_RISCV_RUNTIME_CONST_H
 #define _ASM_RISCV_RUNTIME_CONST_H
 
+#ifdef MODULE
+  #error "Cannot use runtime-const infrastructure from modules"
+#endif
+
 #include <asm/asm.h>
 #include <asm/alternative.h>
 #include <asm/cacheflush.h>
-- 
2.51.0
Re: [PATCH] riscv: make runtime const not usable by modules
Posted by Paul Walmsley 3 weeks, 3 days ago
On Sat, 21 Feb 2026, Jisheng Zhang wrote:

> Similar as commit 284922f4c563 ("x86: uaccess: don't use runtime-const
> rewriting in modules") does, make riscv's runtime const not usable by
> modules too, to "make sure this doesn't get forgotten the next time
> somebody wants to do runtime constant optimizations". The reason is
> well explained in the above commit: "The runtime-const infrastructure
> was never designed to handle the modular case, because the constant
> fixup is only done at boot time for core kernel code."
> 
> Signed-off-by: Jisheng Zhang <jszhang@kernel.org>

Thanks, queued for v7.0-rc.


- Paul