Re: [PATCH] selftests/mm: fix size truncation in pagemap_ioctl test

["David Hildenbrand (Arm)" <david@kernel.org>]

On 9/7/26 15:56, Zenghui Yu wrote:
> From: "Zenghui Yu (Huawei)" <zenghui.yu@linux.dev>
> 
> On arm64 with 64K base pages, the huge page size is 512 MiB, and
> hpage_unit_tests() builds a 5 GiB range (10 * 512 MiB) for its tests.  This
> exceeds the range of the int size parameters of gethugepage(),
> wp_addr_range() and pagemap_ioctl().  The implicit truncation to 1 GiB
> makes gethugepage() allocate a too small buffer, while the callers keep
> operating on the original 5 GiB range, resulting in spurious failures or
> SIGSEGV.
> 
> Change those size parameters to size_t.
> 
> Fixes: 46fd75d4a3c9 ("selftests: mm: add pagemap ioctl tests")
> Assisted-by: GLM-5.3 OpenCode
> Signed-off-by: Zenghui Yu (Huawei) <zenghui.yu@linux.dev>
> ---

Looking at pagemap_ioctl.c ... I think most functions should actually be "static".


Using size_t is ok. But then we should also change "unsigned long long mem_size"
to size_t, no?

Also, in wp_free() we are suddenly using "long size". In pagemap_ioc() we're
also still using "int len".

Can we consistently use one type please?

-- 
Cheers,

David