From: "Dr. David Alan Gilbert" <dgilbert@redhat.com>
To: Wei Yang <richardw.yang@linux.intel.com>, rth@twiddle.net
Cc: pbonzini@redhat.com, qemu-devel@nongnu.org, quintela@redhat.com
Subject: Re: [Qemu-devel] [PATCH] migration: check length directly to make sure the range is aligned
Date: Fri, 19 Jul 2019 18:54:00 +0100 [thread overview]
Message-ID: <20190719175400.GJ3000@work-vm> (raw)
In-Reply-To: <20190712032704.7826-1-richardw.yang@linux.intel.com>
* Wei Yang (richardw.yang@linux.intel.com) wrote:
> Since the start addr is already checked, to make sure the range is
> aligned, checking the length is enough.
>
> Signed-off-by: Wei Yang <richardw.yang@linux.intel.com>
> ---
> exec.c | 7 +++----
> 1 file changed, 3 insertions(+), 4 deletions(-)
>
> diff --git a/exec.c b/exec.c
> index 50ea9c5aaa..8fa980baae 100644
> --- a/exec.c
> +++ b/exec.c
> @@ -4067,10 +4067,9 @@ int ram_block_discard_range(RAMBlock *rb, uint64_t start, size_t length)
>
> if ((start + length) <= rb->used_length) {
> bool need_madvise, need_fallocate;
> - uint8_t *host_endaddr = host_startaddr + length;
> - if ((uintptr_t)host_endaddr & (rb->page_size - 1)) {
> - error_report("ram_block_discard_range: Unaligned end address: %p",
> - host_endaddr);
> + if (length & (rb->page_size - 1)) {
> + error_report("ram_block_discard_range: Unaligned length: %lx",
> + length);
Yes, I *think* this is safe, we'll need to watch out for any warnings;
David Gibson's balloon fix from February means that the balloon code
should now warn in it's case.
rth: Want to pick this up?
Reviewed-by: Dr. David Alan Gilbert <dgilbert@redhat.com>
> goto err;
> }
>
> --
> 2.17.1
>
--
Dr. David Alan Gilbert / dgilbert@redhat.com / Manchester, UK
next prev parent reply other threads:[~2019-07-19 17:54 UTC|newest]
Thread overview: 11+ messages / expand[flat|nested] mbox.gz Atom feed top
2019-07-12 3:27 [Qemu-devel] [PATCH] migration: check length directly to make sure the range is aligned Wei Yang
2019-07-19 17:54 ` Dr. David Alan Gilbert [this message]
2019-07-19 18:03 ` Paolo Bonzini
2019-07-19 18:06 ` Dr. David Alan Gilbert
2019-10-01 7:54 ` Wei Yang
2019-10-28 1:10 ` Wei Yang
2019-10-29 7:04 ` Dr. David Alan Gilbert
2019-10-29 8:21 ` Wei Yang
2019-11-11 23:19 ` Paolo Bonzini
2019-08-19 2:26 ` Wei Yang
2019-09-13 23:58 ` Wei Yang
Reply instructions:
You may reply publicly to this message via plain-text email
using any one of the following methods:
* Save the following mbox file, import it into your mail client,
and reply-to-all from there: mbox
Avoid top-posting and favor interleaved quoting:
https://en.wikipedia.org/wiki/Posting_style#Interleaved_style
* Reply using the --to, --cc, and --in-reply-to
switches of git-send-email(1):
git send-email \
--in-reply-to=20190719175400.GJ3000@work-vm \
--to=dgilbert@redhat.com \
--cc=pbonzini@redhat.com \
--cc=qemu-devel@nongnu.org \
--cc=quintela@redhat.com \
--cc=richardw.yang@linux.intel.com \
--cc=rth@twiddle.net \
/path/to/YOUR_REPLY
https://kernel.org/pub/software/scm/git/docs/git-send-email.html
* If your mail client supports setting the In-Reply-To header
via mailto: links, try the mailto: link
Be sure your reply has a Subject: header at the top and a blank line
before the message body.
This is a public inbox, see mirroring instructions
for how to clone and mirror all data and code used for this inbox;
as well as URLs for NNTP newsgroup(s).