Trim emails already.. this seems a spreading disease. On Mon, May 18, 2015 at 06:10:20AM -0400, Ulrich Obergfell wrote: > Michal, > > if I understand you correctly, Peter's patch solves the problem for you. > I would like to make you aware of a patch that Don and I posted in April. > > https://lkml.org/lkml/2015/4/22/306 > > watchdog_nmi_enable_all() should not use 'watchdog_user_enabled' at all. > It should rather check the NMI_WATCHDOG_ENABLED bit in 'watchdog_enabled'. > The patch is also in Andrew Morton's queue. > > > http://ozlabs.org/~akpm/mmots/broken-out/watchdog-fix-watchdog_nmi_enable_all.patch > > Peter's patch introduces the same change in watchdog_nmi_enable_all(), > plus some synchronization. However, I'm not sure if we actually need the > synchronization. It is my understanding that {en,dis}able_all() are only > called early during kernel startup via initcall 'fixup_ht_bug': > > kernel_init > { > kernel_init_freeable > { > lockup_detector_init > { > watchdog_enable_all_cpus > smpboot_register_percpu_thread(&watchdog_threads) > } > > do_basic_setup > do_initcalls > do_initcall_level > do_one_initcall > fixup_ht_bug // subsys_initcall(fixup_ht_bug) > { > watchdog_nmi_disable_all > > watchdog_nmi_enable_all > } > } > } > > Peter, > > do we really need the synchronization here?
Well, those are the only current usage sites, but the interface is exposed and should be fully and correctly implemented, otherwise a next user might stumble upon sudden unexpected behaviour. But yes, it appears superfluous for this particular usage. -- To unsubscribe from this list: send the line "unsubscribe linux-kernel" in the body of a message to [email protected] More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/
