Messages in this thread | | | Subject | Re: [PATCH v2] xen/hvc: replace BUG_ON() with negative return value | From | Jan Beulich <> | Date | Wed, 7 Jul 2021 11:57:37 +0200 |
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On 07.07.2021 11:10, Juergen Gross wrote: > Xen frontends shouldn't BUG() in case of illegal data received from > their backends. So replace the BUG_ON()s when reading illegal data from > the ring page with negative return values. > > Signed-off-by: Juergen Gross <jgross@suse.com>
Reviewed-by: Jan Beulich <jbeulich@suse.com>
> --- a/drivers/tty/hvc/hvc_xen.c > +++ b/drivers/tty/hvc/hvc_xen.c > @@ -86,7 +86,11 @@ static int __write_console(struct xencons_info *xencons, > cons = intf->out_cons; > prod = intf->out_prod; > mb(); /* update queue values before going on */
Largely unrelated note: While in general the barriers here may want switching to virt_*mb(), this particular one looks to be too heavy anyway: a read barrier is all that's needed here afaict, just like there's only a write barrier between ring contents and producer writing in __write_console().
And btw, since I've got puzzled by the linuxppc-dev@ in the recipients list, I did look up relevant entries in ./MAINTAINERS. Shouldn't the file be part of "XEN HYPERVISOR INTERFACE"?
Jan
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