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[23.128.96.18]) by mx.google.com with ESMTP id l8si3611592edt.265.2021.02.04.09.44.12; Thu, 04 Feb 2021 09:44:20 -0800 (PST) Received-SPF: pass (google.com: domain of stable-owner@vger.kernel.org designates 23.128.96.18 as permitted sender) client-ip=23.128.96.18; Authentication-Results: mx.google.com; dkim=pass header.i=@linaro.org header.s=google header.b=lrkDfKrm; spf=pass (google.com: domain of stable-owner@vger.kernel.org designates 23.128.96.18 as permitted sender) smtp.mailfrom=stable-owner@vger.kernel.org; dmarc=pass (p=NONE sp=NONE dis=NONE) header.from=linaro.org Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S238200AbhBDRnw (ORCPT + 13 others); Thu, 4 Feb 2021 12:43:52 -0500 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:36752 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S238586AbhBDRbP (ORCPT ); Thu, 4 Feb 2021 12:31:15 -0500 Received: from mail-wr1-x435.google.com (mail-wr1-x435.google.com [IPv6:2a00:1450:4864:20::435]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id DEEFFC0617AA for ; Thu, 4 Feb 2021 09:29:19 -0800 (PST) Received: by mail-wr1-x435.google.com with SMTP id c12so4466684wrc.7 for ; Thu, 04 Feb 2021 09:29:19 -0800 (PST) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=linaro.org; s=google; h=from:to:cc:subject:date:message-id:in-reply-to:references :mime-version:content-transfer-encoding; bh=kpLUGBUL3ePc9LcRSMK136epmeMCkjKyot5g5+ExSZs=; b=lrkDfKrmqKhCtD/jgvCllWo5ju50m/wkQJTuvx7E0r9oQ6VMUclDsay9h080wssrrX CBmHhQyOiLZlowk/io5iyiBY5KK1VsIDm53Mrq0QvlydCrC6sQW/uhEIT0PltlQ6W+iL tozxel+p89Lo6FQ11NuWWTqFJ9k/rSQy5i9S0vixQQwE7M+yS17hKgJwC01LZteMFVJ2 yELnfvwNpwxmwmvMvMRFIoRTAhgXSV1srXz/EjC098m7FFrSWt7Q4CQXBde5R/uhsrz1 rxK1MZwNPUhKyWe6MtUsJIDReMLNZRBeRXb91Kqum2LaGJJFJ5fY0okjnprC7vygahs6 gWjg== X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20161025; h=x-gm-message-state:from:to:cc:subject:date:message-id:in-reply-to :references:mime-version:content-transfer-encoding; bh=kpLUGBUL3ePc9LcRSMK136epmeMCkjKyot5g5+ExSZs=; b=qw+koHEQvOJ/5/N7d/6W37USPGKXj3fwwcxKuTk21wror6/App5LHF46JSiD4rewk2 +kKulR7J3gl0w5GIY+OWsVbHmBPi17oTVnRdzDql93GPkngR9OwXhDbl0/5Kl4mNN+42 UTvHYxjTE9jntKAT1lYyntzIv8yORLY84lRHSScsImbiNVPN4nZkn9AwwXdLGQOFf3eA 8oS/TbQD4hIEaDtJHfrIr1aRG7MvjhTq+pQL6CtFO2jFfxA1ZUHLuTw9xm2wLScKY96e 8e8j4bISRkgc9SBaYDgmnauup2HEy4xK8EkQ+PFY+StPiTa0+JmH62uZe8DdMSolOITu m1zg== X-Gm-Message-State: AOAM5302FJX6HVPXAgFpVm/0otPjqQgnWLilfRkDIUhlzAMmGzIDnhlX ifF0Tjylhh8J0+vvlzm23OC8d/QBrVdeBA== X-Received: by 2002:adf:e50e:: with SMTP id j14mr488496wrm.162.1612459758389; Thu, 04 Feb 2021 09:29:18 -0800 (PST) Received: from dell.default ([91.110.221.188]) by smtp.gmail.com with ESMTPSA id j7sm9641334wrp.72.2021.02.04.09.29.17 (version=TLS1_3 cipher=TLS_AES_256_GCM_SHA384 bits=256/256); Thu, 04 Feb 2021 09:29:17 -0800 (PST) From: Lee Jones To: stable@vger.kernel.org Cc: Thomas Gleixner , Peter Zijlstra , Lee Jones Subject: [PATCH 09/10] futex: Simplify fixup_pi_state_owner() Date: Thu, 4 Feb 2021 17:29:02 +0000 Message-Id: <20210204172903.2860981-10-lee.jones@linaro.org> X-Mailer: git-send-email 2.25.1 In-Reply-To: <20210204172903.2860981-1-lee.jones@linaro.org> References: <20210204172903.2860981-1-lee.jones@linaro.org> MIME-Version: 1.0 Precedence: bulk List-ID: X-Mailing-List: stable@vger.kernel.org From: Thomas Gleixner [ Upstream commit f2dac39d93987f7de1e20b3988c8685523247ae2 ] Too many gotos already and an upcoming fix would make it even more unreadable. Signed-off-by: Thomas Gleixner Acked-by: Peter Zijlstra (Intel) Cc: stable@vger.kernel.org Signed-off-by: Lee Jones --- kernel/futex.c | 41 +++++++++++++++++++++++++++-------------- 1 file changed, 27 insertions(+), 14 deletions(-) -- 2.25.1 diff --git a/kernel/futex.c b/kernel/futex.c index d9bec8eb60969..8300870666638 100644 --- a/kernel/futex.c +++ b/kernel/futex.c @@ -2237,18 +2237,16 @@ static void unqueue_me_pi(struct futex_q *q) spin_unlock(q->lock_ptr); } -static int fixup_pi_state_owner(u32 __user *uaddr, struct futex_q *q, - struct task_struct *argowner) +static int __fixup_pi_state_owner(u32 __user *uaddr, struct futex_q *q, + struct task_struct *argowner) { struct futex_pi_state *pi_state = q->pi_state; - u32 uval, uninitialized_var(curval), newval; struct task_struct *oldowner, *newowner; - u32 newtid; - int ret; - - lockdep_assert_held(q->lock_ptr); + u32 uval, curval, newval, newtid; + int err = 0; oldowner = pi_state->owner; + /* Owner died? */ if (!pi_state->owner) newtid |= FUTEX_OWNER_DIED; @@ -2289,7 +2287,7 @@ retry: if (__rt_mutex_futex_trylock(&pi_state->pi_mutex)) { /* We got the lock after all, nothing to fix. */ - return 0; + return 1; } /* @@ -2304,7 +2302,7 @@ retry: * We raced against a concurrent self; things are * already fixed up. Nothing to do. */ - return 0; + return 1; } newowner = argowner; } @@ -2345,7 +2343,7 @@ retry: handle_fault: spin_unlock(q->lock_ptr); - ret = fault_in_user_writeable(uaddr); + err = fault_in_user_writeable(uaddr); spin_lock(q->lock_ptr); @@ -2353,12 +2351,27 @@ handle_fault: * Check if someone else fixed it for us: */ if (pi_state->owner != oldowner) - return 0; + return argowner == current; - if (ret) - return ret; + /* Retry if err was -EAGAIN or the fault in succeeded */ + if (!err) + goto retry; - goto retry; + return err; +} + +static int fixup_pi_state_owner(u32 __user *uaddr, struct futex_q *q, + struct task_struct *argowner) +{ + struct futex_pi_state *pi_state = q->pi_state; + int ret; + + lockdep_assert_held(q->lock_ptr); + + raw_spin_lock_irq(&pi_state->pi_mutex.wait_lock); + ret = __fixup_pi_state_owner(uaddr, q, argowner); + raw_spin_unlock_irq(&pi_state->pi_mutex.wait_lock); + return ret; } static long futex_wait_restart(struct restart_block *restart);