Re: [PATCH v9 1/8] kexec_file: allow to place kexec_buf randomly

On Wed, Aug 27, 2025 at 07:38:29PM +0800, Baoquan He wrote:

On 08/25/25 at 06:05pm, Andrew Morton wrote:

quoted

On Mon, 25 Aug 2025 09:18:53 +0800 Coiby Xu [off-list ref] wrote:

quoted

quoted

diff --git a/arch/arm64/kernel/kexec_image.c b/arch/arm64/kernel/kexec_image.c
index 532d72ea42ee8..287b25e674d76 100644
--- a/arch/arm64/kernel/kexec_image.c
+++ b/arch/arm64/kernel/kexec_image.c

@@ -76,6 +76,7 @@ static void *image_load(struct kimage *image,

	kbuf.buf_min = 0;
	kbuf.buf_max = ULONG_MAX;
	kbuf.top_down = false;
+	kbuf.random = 0;

	kbuf.buffer = kernel;
	kbuf.bufsz = kernel_len;

And also thanks for posing a fix! The patch LGTM. Can you add a Fixes
tag 'Fixes: bf454ec31add ("kexec_file: allow to place kexec_buf
randomly")' and then send it to kexec@lists.infradead.org? Thanks!

I turned all this into a regular patch and queued it (see below),
thanks.  No additional actions are needed.

I'm really not liking that code.  I laboriously verified that all
fields of kexec_buf are now initialized, except for `cma'.  Is that a
bug?

This function has a call frequency of about 3x per week.  Can we please
just memset the whole thing so people don't have to worry about this
any more?

Yeah, adding these trivial patches to mute XXSAN warning is annoying.

The patchset is quite simple, tho:

https://lore.kernel.org/all/20250827-kbuf_all-v1-0-1df9882bb01a@debian.org/ (local)