From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: X-Spam-Checker-Version: SpamAssassin 3.4.0 (2014-02-07) on aws-us-west-2-korg-lkml-1.web.codeaurora.org Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by smtp.lore.kernel.org (Postfix) with ESMTP id 49EA5C4332F for ; Mon, 11 Apr 2022 11:50:26 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1345705AbiDKLwh (ORCPT ); Mon, 11 Apr 2022 07:52:37 -0400 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:38444 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S242979AbiDKLwf (ORCPT ); Mon, 11 Apr 2022 07:52:35 -0400 Received: from mail-qt1-x831.google.com (mail-qt1-x831.google.com [IPv6:2607:f8b0:4864:20::831]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id 8461A45AD8 for ; Mon, 11 Apr 2022 04:50:21 -0700 (PDT) Received: by mail-qt1-x831.google.com with SMTP id z14so1831873qto.5 for ; Mon, 11 Apr 2022 04:50:21 -0700 (PDT) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=ziepe.ca; s=google; h=date:from:to:cc:subject:message-id:references:mime-version :content-disposition:in-reply-to; bh=nYKlpbInSVi2kWjadcO+xwlKXyAqxDdBQNrxNvWjuVU=; b=Hx94opGZFvJS4PSHhQFprTvwYfvoh3pFGcECifD9kOhnQVfGZJu1X4ZeZbCAc4yCB1 S9b7nSzC9fgbeC9V23xRQVY+iiCZK8a4UJ8kBSzP6j+69zX9OH+MBzosaKiwlBhd9hPO TNgQPZ26NKkBfYYO3VK1hY22AxgahsXkBZQxj0tgcNErzwfImBHJ21ry7WEP0FyPe4dk f4E4E9jti0Jr+jJj69mXLrDZcAeCUmPU1Qe2HVpEBHhSp22KoV/sJFOncfIPS0Wlf4Sf wNcneO9B4xkd/xdC1wd3eYUyY21oHuo/DBsOhk6IrP/ubUeaSvRb2alqBgWnKS6eDRoF THxg== X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20210112; h=x-gm-message-state:date:from:to:cc:subject:message-id:references :mime-version:content-disposition:in-reply-to; bh=nYKlpbInSVi2kWjadcO+xwlKXyAqxDdBQNrxNvWjuVU=; b=d2b4R0tihhmsGEka3706Kz1w20I/VzXXMeE304fCvHp6npUQK8SdRKo8g0tuuCzu3k azuLowsBTvEkbQj3jcWODPWHmhDsAcBaXFVI95cEAKJFGROzgsGSHp35tbv7LHO808h+ 8DnoAsNrJBCFnn34vMx5o+AW75kq8s0uLtZltMs0ISoo2VaMW2viSt3kiuul4/oikOn0 rb2MIQrUoEJxjlCzbdz1CjWhGHL4p4GbWrBOpMf37yX8jVWaRtVWS2oU5Jcj5TK3Dbbl zwR/Uuf7R4fhQnhh8dTJFXhw2YmnwgjDUpastanOuMLhSgYiLCYYVWPv61D32VSIYld8 hB8Q== X-Gm-Message-State: AOAM531yMY/sfVcsrXJQXKyA84DFqDZ9QhV8dPsLfK3PGJUvCRiGE5pY 5jNLfirYELnR3U7FIOJe9dtk3g== X-Google-Smtp-Source: ABdhPJxSfBoB+/zEXxpz+SssqmVIVy8y/b3XOQ1QxT0jEktgkc2EaT+HL41RN7fRIfpbuB7wwdkvGA== X-Received: by 2002:ac8:5a86:0:b0:2ed:1434:4492 with SMTP id c6-20020ac85a86000000b002ed14344492mr6008916qtc.17.1649677820682; Mon, 11 Apr 2022 04:50:20 -0700 (PDT) Received: from ziepe.ca (hlfxns017vw-142-162-113-129.dhcp-dynamic.fibreop.ns.bellaliant.net. [142.162.113.129]) by smtp.gmail.com with ESMTPSA id q123-20020a378e81000000b0067eb3d6f605sm18704645qkd.0.2022.04.11.04.50.19 (version=TLS1_3 cipher=TLS_AES_256_GCM_SHA384 bits=256/256); Mon, 11 Apr 2022 04:50:19 -0700 (PDT) Received: from jgg by mlx with local (Exim 4.94) (envelope-from ) id 1ndsYl-00Gj15-9z; Mon, 11 Apr 2022 08:50:19 -0300 Date: Mon, 11 Apr 2022 08:50:19 -0300 From: Jason Gunthorpe To: yanjun.zhu@linux.dev Cc: zyjzyj2000@gmail.com, leon@kernel.org, linux-rdma@vger.kernel.org, Yi Zhang Subject: Re: [PATCHv2 1/1] RDMA/rxe: Fix a dead lock problem Message-ID: <20220411115019.GB64706@ziepe.ca> References: <20220411200018.1363127-1-yanjun.zhu@linux.dev> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <20220411200018.1363127-1-yanjun.zhu@linux.dev> Precedence: bulk List-ID: X-Mailing-List: linux-rdma@vger.kernel.org On Mon, Apr 11, 2022 at 04:00:18PM -0400, yanjun.zhu@linux.dev wrote: > @@ -138,8 +139,10 @@ void *rxe_alloc(struct rxe_pool *pool) > elem->obj = obj; > kref_init(&elem->ref_cnt); > > - err = xa_alloc_cyclic(&pool->xa, &elem->index, elem, pool->limit, > - &pool->next, GFP_KERNEL); > + xa_lock_irqsave(&pool->xa, flags); > + err = __xa_alloc_cyclic(&pool->xa, &elem->index, elem, pool->limit, > + &pool->next, GFP_ATOMIC); > + xa_unlock_irqrestore(&pool->xa, flags); No to using atomics, this needs to be either the _irq or _bh varient Jason