From mboxrd@z Thu Jan 1 00:00:00 1970 Date: Mon, 27 Aug 2007 14:43:46 -0700 (PDT) From: Christoph Lameter Subject: Re: [patch 1/1] alloc_pages(): permit get_zeroed_page(GFP_ATOMIC) from interrupt context In-Reply-To: <20070827143459.82bdeddd.akpm@linux-foundation.org> Message-ID: References: <200708232107.l7NL7XDt026979@imap1.linux-foundation.org> <20070827133347.424f83a6.akpm@linux-foundation.org> <20070827140440.d2109ea5.akpm@linux-foundation.org> <20070827143459.82bdeddd.akpm@linux-foundation.org> MIME-Version: 1.0 Content-Type: TEXT/PLAIN; charset=US-ASCII Sender: owner-linux-mm@kvack.org Return-Path: To: Andrew Morton Cc: linux-mm@kvack.org, Ingo Molnar , thomas.jarosch@intra2net.com List-ID: On Mon, 27 Aug 2007, Andrew Morton wrote: > > Move the check for highmem to the beginning of the function? Why > > should kmap_atomic fail for a non highmem page? > > For test coverage, mainly. If someone is testing highmem-enabled code on > a 512MB machine, we want them to get told about any highmem-handling bugs, > even though they don't have highmem. But the test is for nested kmap_atomics. Nesting (at least allocate a regular page while highmem page is being mapped) needs to work in order to be able to allocate a page from an interrupt contexts. -- To unsubscribe, send a message with 'unsubscribe linux-mm' in the body to majordomo@kvack.org. For more info on Linux MM, see: http://www.linux-mm.org/ . Don't email: email@kvack.org