Re: [Xen-devel] [PATCH] xenconsole: Ensure exclusive access to console using locks

2015-07-24 Thread Ian Campbell
On Fri, 2015-07-24 at 15:40 +0200, Martin Lucina wrote: > On Friday, 24.07.2015 at 14:11, Ian Campbell wrote: > > I'm afraid this (delving into another components private headers) isn't > > allowed. Instead you should add the two lines to tools/console/Makefile > > to generate a local _paths.h: > >

Re: [Xen-devel] [PATCH] xenconsole: Ensure exclusive access to console using locks

2015-07-24 Thread Ian Campbell
On Fri, 2015-07-24 at 14:32 +0100, Ian Jackson wrote: > > > > +static void console_lock(int domid) > > +{ > > + lockfile = malloc(PATH_MAX); > > + if (lockfile == NULL) > > + err(ENOMEM, "malloc"); > > + snprintf(lockfile, PATH_MAX - 1, "%s/xenconsole.%d", > > XEN_LOCK_DIR, domid

Re: [Xen-devel] [PATCH] xenconsole: Ensure exclusive access to console using locks

2015-07-24 Thread Martin Lucina
On Friday, 24.07.2015 at 14:32, Ian Jackson wrote: > > +static void console_lock(int domid) > > +{ > > + lockfile = malloc(PATH_MAX); > > + if (lockfile == NULL) > > + err(ENOMEM, "malloc"); > > + snprintf(lockfile, PATH_MAX - 1, "%s/xenconsole.%d", XEN_LOCK_DIR, > > domid); > > W

Re: [Xen-devel] [PATCH] xenconsole: Ensure exclusive access to console using locks

2015-07-24 Thread Martin Lucina
On Friday, 24.07.2015 at 14:11, Ian Campbell wrote: > I'm afraid this (delving into another components private headers) isn't > allowed. Instead you should add the two lines to tools/console/Makefile > to generate a local _paths.h: > > genpath-target = $(call buildmakevars2header,_paths.h) > $(eva

Re: [Xen-devel] [PATCH] xenconsole: Ensure exclusive access to console using locks

2015-07-24 Thread Ian Jackson
Ian Campbell writes ("Re: [PATCH] xenconsole: Ensure exclusive access to console using locks"): > I think the answer is to either not remove the lockfile That is a bit messy (although not entirely wrong). > or to do so _before_ dropping the lock, which makes the unlink > itself the effective unl

Re: [Xen-devel] [PATCH] xenconsole: Ensure exclusive access to console using locks

2015-07-24 Thread Ian Jackson
Martin Lucina writes ("[PATCH] xenconsole: Ensure exclusive access to console using locks"): > If more than one instance of xenconsole is run against the same DOMID > then each instance will only get some data. This change ensures > exclusive access to the console by creating and obtaining an excl

Re: [Xen-devel] [PATCH] xenconsole: Ensure exclusive access to console using locks

2015-07-24 Thread Ian Campbell
On Fri, 2015-07-24 at 14:51 +0200, Martin Lucina wrote: > If more than one instance of xenconsole is run against the same DOMID > then each instance will only get some data. This change ensures > exclusive access to the console by creating and obtaining an > exclusive > lock on /xenconsole.. > >

[Xen-devel] [PATCH] xenconsole: Ensure exclusive access to console using locks

2015-07-24 Thread Martin Lucina
If more than one instance of xenconsole is run against the same DOMID then each instance will only get some data. This change ensures exclusive access to the console by creating and obtaining an exclusive lock on /xenconsole.. Signed-off-by: Martin Lucina Cc: Ian Jackson Cc: Stefano Stabellini