Messages in this thread | | | Subject | RE: [uml-devel] [PATCH 19/19] UML - Make mconsole version requestshappen in a process | Date | Fri, 7 Jul 2006 08:31:50 -0700 | From | "Brock, Anthony - NET" <> |
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So what impact does this have on the following quote from http://user-mode-linux.sourceforge.net/mconsole.html :
It's a simple no-op which can be used to check that a UML is running. It's also a way of sending an interrupt to the UML. This is sometimes useful on SMP hosts, where there's a bug which causes signals to UML to be lost, often causing it to appear to hang. Sending such a UML the mconsole version command is a good way to 'wake it up' before networking has been enabled, as it does not do anything to the function of the UML.
I'm running UML on an SMP machine, but have never encountered the "hang" issue. Is this text still accurate? Also, can this command still be used to "wake up" a UML process? Is this still the recommended means for verifying that a UML process if running?
Tony
> -----Original Message----- > From: user-mode-linux-devel-bounces@lists.sourceforge.net > [mailto:user-mode-linux-devel-bounces@lists.sourceforge.net] > On Behalf Of Jeff Dike > Sent: Thursday, July 06, 2006 5:34 PM > To: akpm@osdl.org > Cc: linux-kernel@vger.kernel.org; > user-mode-linux-devel@lists.sourceforge.net > Subject: [uml-devel] [PATCH 19/19] UML - Make mconsole > version requestshappen in a process > > Handling a host mconsole version request must be done in a > process context > rather than interrupt context now that utsname information can be > process-specific rather than global. > > Signed-off-by: Jeff Dike <jdike@addtoit.com> > > Index: linux-2.6.16/arch/um/drivers/mconsole_user.c > =================================================================== > --- linux-2.6.16.orig/arch/um/drivers/mconsole_user.c > +++ linux-2.6.16/arch/um/drivers/mconsole_user.c > @@ -18,7 +18,12 @@ > #include "umid.h" > > static struct mconsole_command commands[] = { > - { "version", mconsole_version, MCONSOLE_INTR }, > + /* With uts namespaces, uts information becomes > process-specific, so > + * we need a process context. If we try handling this > in interrupt > + * context, we may hit an exiting process without a valid uts > + * namespace. > + */ > + { "version", mconsole_version, MCONSOLE_PROC }, > { "halt", mconsole_halt, MCONSOLE_PROC }, > { "reboot", mconsole_reboot, MCONSOLE_PROC }, > { "config", mconsole_config, MCONSOLE_PROC }, > > > Using Tomcat but need to do more? Need to support web > services, security? > Get stuff done quickly with pre-integrated technology to make > your job easier > Download IBM WebSphere Application Server v.1.0.1 based on > Apache Geronimo > http://sel.as-us.falkag.net/sel?cmd=lnk&kid=120709&bid=263057& > dat=121642 > _______________________________________________ > User-mode-linux-devel mailing list > User-mode-linux-devel@lists.sourceforge.net > https://lists.sourceforge.net/lists/listinfo/user-mode-linux-devel > - To unsubscribe from this list: send the line "unsubscribe linux-kernel" in the body of a message to majordomo@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/
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