On 11/19/25 7:38 PM, David Hildenbrand (Red Hat) wrote:
On 19.11.25 08:31, Qi Zheng wrote:
From: Qi Zheng <[email protected]>
Now, the MMU_GATHER_RCU_TABLE_FREE is enabled on all 64-bit
architectures,
so make PT_RECLAIM depend on 64BIT, thereby enabling PT_RECLAIM on all
64-bit architectures.
Signed-off-by: Qi Zheng <[email protected]>
---
arch/x86/Kconfig | 1 -
mm/Kconfig | 9 ++-------
2 files changed, 2 insertions(+), 8 deletions(-)
diff --git a/arch/x86/Kconfig b/arch/x86/Kconfig
index eac2e86056902..96bff81fd4787 100644
--- a/arch/x86/Kconfig
+++ b/arch/x86/Kconfig
@@ -330,7 +330,6 @@ config X86
select FUNCTION_ALIGNMENT_4B
imply IMA_SECURE_AND_OR_TRUSTED_BOOT if EFI
select HAVE_DYNAMIC_FTRACE_NO_PATCHABLE
- select ARCH_SUPPORTS_PT_RECLAIM if X86_64
select ARCH_SUPPORTS_SCHED_SMT if SMP
select SCHED_SMT if SMP
select ARCH_SUPPORTS_SCHED_CLUSTER if SMP
diff --git a/mm/Kconfig b/mm/Kconfig
index d548976d0e0ad..94eec5c0cad96 100644
--- a/mm/Kconfig
+++ b/mm/Kconfig
@@ -1448,14 +1448,9 @@ config ARCH_HAS_USER_SHADOW_STACK
The architecture has hardware support for userspace shadow call
stacks (eg, x86 CET, arm64 GCS or RISC-V Zicfiss).
-config ARCH_SUPPORTS_PT_RECLAIM
- def_bool n
-
config PT_RECLAIM
- bool "reclaim empty user page table pages"
- default y
- depends on ARCH_SUPPORTS_PT_RECLAIM && MMU && SMP
- select MMU_GATHER_RCU_TABLE_FREE
+ def_bool y
+ depends on 64BIT
As discussed in the other thread, likely
config PT_RECLAIM
def_bool y
depends on MMU_GATHER_RCU_TABLE_FREE && 64BIT
Could be nice, and if possible even dropping the 64BIT limitation as
well if there is no need to.
I think it's ok to drop the 64BIT limitation. There should be some
32-bit architectures that already enable MMU_GATHER_RCU_TABLE_FREE.
