From mboxrd@z Thu Jan 1 00:00:00 1970 From: Benjamin LaHaise Subject: Re: [PATCH aio-next] aio: fix error handling and rcu usage in "convert the ioctx list to table lookup v3" Date: Tue, 6 Aug 2013 20:52:04 -0400 Message-ID: <20130807005204.GF8043@kvack.org> References: <51FFAF34.20200@oracle.com> <20130805160828.GH31864@kvack.org> <20130805172032.GI31864@kvack.org> <5201714C.8000100@oracle.com> Mime-Version: 1.0 Return-path: Content-Disposition: inline In-Reply-To: <5201714C.8000100@oracle.com> Sender: owner-linux-aio@kvack.org List-ID: Content-Type: text/plain; charset="us-ascii" Content-Transfer-Encoding: 7bit To: Sasha Levin Cc: Kent Overstreet , axboe@kernel.dk, Andrew Morton , torvalds@linux-foundation.org, LKML , linux-aio@kvack.org, trinity@vger.kernel.org On Tue, Aug 06, 2013 at 05:57:32PM -0400, Sasha Levin wrote: > Old error is gone, but now seeing this, which seems related. > > ctx = table->table[id]; > if (ctx->user_id == ctx_id) { <--- here > percpu_ref_get(&ctx->users); > ret = ctx; > } ... Why am I not surprised. That should be fixed with the patch below. I'll post some patches for the libaio test suite tomorrow to check these cases explicitly and scan for any others that need to be added. Thanks again, Sasha. -ben -- "Thought is the essence of where you are now." diff --git a/fs/aio.c b/fs/aio.c index 3bc068c..c3f005d 100644 --- a/fs/aio.c +++ b/fs/aio.c @@ -812,7 +812,7 @@ static struct kioctx *lookup_ioctx(unsigned long ctx_id) goto out; ctx = table->table[id]; - if (ctx->user_id == ctx_id) { + if (ctx && ctx->user_id == ctx_id) { percpu_ref_get(&ctx->users); ret = ctx; } -- To unsubscribe, send a message with 'unsubscribe linux-aio' in the body to majordomo@kvack.org. For more info on Linux AIO, see: http://www.kvack.org/aio/ Don't email: aart@kvack.org