From mboxrd@z Thu Jan 1 00:00:00 1970 From: Arnd Bergmann Subject: [PATCH] [RFC] mm/page_ref, crypto/async_pq: don't put_page from __exit Date: Sun, 28 Feb 2016 22:57:23 +0100 Message-ID: <1456696663-2340682-1-git-send-email-arnd@arndb.de> Cc: linux-arm-kernel@lists.infradead.org, Michal Nazarewicz , Steven Rostedt , Andrew Morton , Arnd Bergmann , Dan Williams , Herbert Xu , "David S. Miller" , linux-crypto@vger.kernel.org, linux-kernel@vger.kernel.org To: Joonsoo Kim , linux-mm@kvack.org Return-path: Received: from mout.kundenserver.de ([217.72.192.75]:50717 "EHLO mout.kundenserver.de" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1755040AbcB1V7Q (ORCPT ); Sun, 28 Feb 2016 16:59:16 -0500 Sender: linux-crypto-owner@vger.kernel.org List-ID: The addition of tracepoints to the page reference tracking had an unfortunate side-effect in at least one driver that calls put_page from its exit function, resulting in a link error: `.exit.text' referenced in section `__jump_table' of crypto/built-in.o: defined in discarded section `.exit.text' of crypto/built-in.o I could not come up with a nice solution that ignores __jump_table entries in discarded code, so we probably now have to treat this as something a driver is not allowed to do. Removing the __exit annotation avoids the problem in this particular driver, but the same problem could come back any time in other code. On a related problem regarding the runtime patching for SMP operations on ARM uniprocessor systems, we resorted to not drop the .exit section at link time, but that doesn't seem appropriate here. Signed-off-by: Arnd Bergmann Fixes: 0f80830dd044 ("mm/page_ref: add tracepoint to track down page reference manipulation") --- crypto/async_tx/async_pq.c | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-) diff --git a/crypto/async_tx/async_pq.c b/crypto/async_tx/async_pq.c index c0748bbd4c08..be167145aa55 100644 --- a/crypto/async_tx/async_pq.c +++ b/crypto/async_tx/async_pq.c @@ -442,7 +442,7 @@ static int __init async_pq_init(void) return -ENOMEM; } -static void __exit async_pq_exit(void) +static void async_pq_exit(void) { put_page(pq_scribble_page); } -- 2.7.0