From mboxrd@z Thu Jan 1 00:00:00 1970 From: Jes Sorensen Date: Wed, 20 Dec 2006 09:48:54 +0000 Subject: Re: [patch 3/3] IA64: virt_to_page() can be called with NULL arg Message-Id: <45890706.7070002@sgi.com> List-Id: References: <200612192104.kBJL4iBg010376@shell0.pdx.osdl.net> In-Reply-To: <200612192104.kBJL4iBg010376@shell0.pdx.osdl.net> MIME-Version: 1.0 Content-Type: text/plain; charset="us-ascii" Content-Transfer-Encoding: 7bit To: linux-ia64@vger.kernel.org Kirill Korotaev wrote: >>>>>>> "akpm" = akpm writes: >> >> akpm> From: Kirill Korotaev It does not return NULL >> akpm> when arg is NULL. >> >> Shouldn't the real fix be to track down who calls virt_to_page() with >> a NULL pointer? IMHO it is bogus to do so. > what do you propose? to insert BUG_ON(!kaddr) into virt_to_page()? > in this case caller in question should be still fixed. If you hit this, yes I'd insert the BUG_ON in your test kernel and fix the code. Maybe add the BUG_ON in upstream for CONFIG_DEBUG or something. Which callers did you see cause this? If it was a common problem I would expect a lot of data corruption or crashes on ia64 systems which I haven't heard of. Cheers, Jes