lists  /  announce  owl-users  owl-dev  john-users  john-dev  passwdqc-users  yescrypt  popa3d-users  /  oss-security  kernel-hardening  musl  sabotage  tlsify  passwords  /  crypt-dev  xvendor  /  Bugtraq  Full-Disclosure  linux-kernel  linux-netdev  linux-ext4  linux-hardening  PHC 
Open Source and information security mailing list archives
Hash Suite for Android: free password hash cracker in your pocket
[<prev] [next>] [<thread-prev] [thread-next>] [day] [month] [year] [list]
Date:   Mon, 17 Oct 2022 14:03:11 -0300
From:   Jason Gunthorpe <>
To:     Christian Schoenebeck <>
        Dominique Martinet <>,
        Eric Van Hensbergen <>,
        Latchesar Ionkov <>,
        Nikolay Kichukov <>,
        Leon Romanovsky <>
Subject: Re: [PATCH v6 11/11] net/9p: allocate appropriate reduced message

On Fri, Jul 15, 2022 at 11:33:56PM +0200, Christian Schoenebeck wrote:
> So far 'msize' was simply used for all 9p message types, which is far
> too much and slowed down performance tremendously with large values
> for user configurable 'msize' option.
> Let's stop this waste by using the new p9_msg_buf_size() function for
> allocating more appropriate, smaller buffers according to what is
> actually sent over the wire.
> Only exception: RDMA transport is currently excluded from this message
> size optimization - for its response buffers that is - as RDMA transport
> would not cope with it, due to its response buffers being pulled from a
> shared pool. [1]
> Link: [1]
> Signed-off-by: Christian Schoenebeck <>
> ---
>  net/9p/client.c | 42 +++++++++++++++++++++++++++++++++++-------
>  1 file changed, 35 insertions(+), 7 deletions(-)

It took me a while to sort out, but for any others - this patch is
incompatible with qemu 5.0. It starts working again after this qemu

commit cf45183b718f02b1369e18c795dc51bc1821245d
Author: Stefano Stabellini <>
Date:   Thu May 21 12:26:25 2020 -0700

    Revert "9p: init_in_iov_from_pdu can truncate the size"
    This reverts commit 16724a173049ac29c7b5ade741da93a0f46edff7.
    It causes
    Signed-off-by: Stefano Stabellini <>
    Reviewed-by: Christian Schoenebeck <>
    Message-Id: <>
    Signed-off-by: Greg Kurz <>

It causes something like this:

# modprobe ib_cm
qemu-system-x86_64: VirtFS reply type 117 needs 17 bytes, buffer has 17, less than minimum


Powered by blists - more mailing lists