Re: [PATCH] [v2] mm: shmem: avoid build warning for CONFIG_SHMEM=n

From: Baolin Wang

Date: Thu Dec 04 2025 - 07:38:18 EST




On 2025/12/4 18:28, Arnd Bergmann wrote:
From: Arnd Bergmann <arnd@xxxxxxxx>

The newly added 'flags' variable is unused and causes a warning if
CONFIG_SHMEM is disabled, since the shmem_acct_size() macro it is passed
into does nothing:

mm/shmem.c: In function '__shmem_file_setup':
mm/shmem.c:5816:23: error: unused variable 'flags' [-Werror=unused-variable]
5816 | unsigned long flags = (vm_flags & VM_NORESERVE) ? SHMEM_F_NORESERVE : 0;
| ^~~~~

Replace the two macros with equivalent inline functions tto get the
argument checking.

Fixes: 6ff1610ced56 ("mm: shmem: use SHMEM_F_* flags instead of VM_* flags")
Signed-off-by: Arnd Bergmann <arnd@xxxxxxxx>
---
v2: make shmem_unacct_size() inline as well.
---

LGTM. Thanks.
Reviewed-by: Baolin Wang <baolin.wang@xxxxxxxxxxxxxxxxx>