From mboxrd@z Thu Jan  1 00:00:00 1970
From: Andrew Cooper <andrew.cooper3@citrix.com>
Subject: Re: [PATCH 2/2] build: convert NR_CPUS to Kconfig
Date: Sat, 9 Jan 2016 14:36:48 +0000
Message-ID: <56911B00.20307@citrix.com>
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To: Doug Goldstein <cardoe@cardoe.com>, xen-devel@lists.xen.org
Cc: Keir Fraser <keir@xen.org>, Ian Campbell <ian.campbell@citrix.com>, George Dunlap <george.dunlap@eu.citrix.com>, Liu Jinsong <jinsong.liu@alibaba-inc.com>, Dario Faggioli <dario.faggioli@citrix.com>, Stefano Stabellini <stefano.stabellini@citrix.com>, Jan Beulich <jbeulich@suse.com>
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On 08/01/16 23:17, Doug Goldstein wrote:
> diff --git a/xen/common/spinlock.c b/xen/common/spinlock.c
> index 7f89694..9207179 100644
> --- a/xen/common/spinlock.c
> +++ b/xen/common/spinlock.c
> @@ -246,7 +246,7 @@ int _spin_trylock_recursive(spinlock_t *lock)
>      unsigned int cpu = smp_processor_id();
>  
>      /* Don't allow overflow of recurse_cpu field. */
> -    BUILD_BUG_ON(NR_CPUS > 0xfffu);
> +    BUILD_BUG_ON(CONFIG_NR_CPUS > 0xfffu);
>  
>      check_lock(&lock->debug);
>  

Talking of recursive spinlocks, this check has a fencepost error.

I have submitted a cleanup patch, subject "xen/spinlock: Use mnemonics
for recursive spinlock sentinel values", which also fixes this bug.

It is going to conflict with this change.  I don't mind rebasing,
depending on which patch gets accepted first.

Everything else looks fine.  Reviewed-by: Andrew Cooper
<andrew.cooper3@citrix.com>