Re: [PATCH RFC PKS/PMEM 51/58] kernel: Utilize new kmap_thread()

[ebiederm@xxxxxxxxxxxx (Eric W. Biederman)]

ira.weiny@xxxxxxxxx writes:

> From: Ira Weiny <ira.weiny@xxxxxxxxx>
>
> This kmap() call is localized to a single thread.  To avoid the over
> head of global PKRS updates use the new kmap_thread() call.

Acked-by: "Eric W. Biederman" <ebiederm@xxxxxxxxxxxx>

>
> Cc: Eric Biederman <ebiederm@xxxxxxxxxxxx>
> Signed-off-by: Ira Weiny <ira.weiny@xxxxxxxxx>
> ---
>  kernel/kexec_core.c | 8 ++++----
>  1 file changed, 4 insertions(+), 4 deletions(-)
>
> diff --git a/kernel/kexec_core.c b/kernel/kexec_core.c
> index c19c0dad1ebe..272a9920c0d6 100644
> --- a/kernel/kexec_core.c
> +++ b/kernel/kexec_core.c
> @@ -815,7 +815,7 @@ static int kimage_load_normal_segment(struct kimage 
> *image,
>               if (result < 0)
>                       goto out;
>  
> -             ptr = kmap(page);
> +             ptr = kmap_thread(page);
>               /* Start with a clear page */
>               clear_page(ptr);
>               ptr += maddr & ~PAGE_MASK;
> @@ -828,7 +828,7 @@ static int kimage_load_normal_segment(struct kimage 
> *image,
>                       memcpy(ptr, kbuf, uchunk);
>               else
>                       result = copy_from_user(ptr, buf, uchunk);
> -             kunmap(page);
> +             kunmap_thread(page);
>               if (result) {
>                       result = -EFAULT;
>                       goto out;
> @@ -879,7 +879,7 @@ static int kimage_load_crash_segment(struct kimage *image,
>                       goto out;
>               }
>               arch_kexec_post_alloc_pages(page_address(page), 1, 0);
> -             ptr = kmap(page);
> +             ptr = kmap_thread(page);
>               ptr += maddr & ~PAGE_MASK;
>               mchunk = min_t(size_t, mbytes,
>                               PAGE_SIZE - (maddr & ~PAGE_MASK));
> @@ -895,7 +895,7 @@ static int kimage_load_crash_segment(struct kimage *image,
>               else
>                       result = copy_from_user(ptr, buf, uchunk);
>               kexec_flush_icache_page(page);
> -             kunmap(page);
> +             kunmap_thread(page);
>               arch_kexec_pre_free_pages(page_address(page), 1);
>               if (result) {
>                       result = -EFAULT;