From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: X-Google-Smtp-Source: AH8x227zimGyIeyU9e0VnP4Jajzfikweur4yN5OoFSlYWcnjhf06zZSH20hz6dDu3rMG8NFHB0Sf ARC-Seal: i=1; a=rsa-sha256; t=1518708529; cv=none; d=google.com; s=arc-20160816; b=AUVaj9rczoYb7iom7ZSkgoNfrUDXTWbUUU2bw+D9+UwdBAH85yuR3WKt5cL8QlhJGK lyTZOe3AxAvO94dLVNn0P87ZDsBKm5kVX6glhDQ0To1Htqub59K0s81XiUyatU/KMqaU uFautdjgzD0jib1oNRYkmCYSETy5YRotWF0HeN32734pamZShxzo5ztlqlaesIbN9Akg 3IVBM4HF+PjNDaafZ0sY5oZRiUv/nAXMP/Mk8d1Uj8aKXYUPhqHavCKnFpY96F36DNs8 FHcOmSZuDLRl7QmPa+teg9Me0dAl0gbnGf5+WyrutDpuA4wxpsAM0BnfKc/ixHtmIe+/ yQ0g== ARC-Message-Signature: i=1; a=rsa-sha256; c=relaxed/relaxed; d=google.com; s=arc-20160816; h=mime-version:user-agent:references:in-reply-to:message-id:date :subject:cc:to:from:arc-authentication-results; bh=0WD61r2GtsgbY/fhR/l4/+g6eXpc0kLGJD9XBr9XCv0=; b=yxwUw75fF1F5258FpcZRTaee5RdWn3WoPQI29E0onstIgIfdJg+nx0x/lWQryGEDn1 qbYom5kuhVyDb2AM8BIVvIV6yZvhyCIC1ktG1Cd2k+sa9lnJ9dwx4PzJz3ftIP1pEO1M uXzRj2ywFQXJrLLtcJgZFr4BMdNOh+3YaIOGW3FpOoM/gpnH/hIAnewKggHREwJpZGBe lwZigCywQjuNZ+h4Ac3wryQZ9au7AtubE2+Sfk+RH4R4/ugZu0x2xU+6LUqhrBJnd0q2 IlzcRZY7SFuRlkfdVHZXMTpsdTdD9i6RUZdaLgSwgZjjYjQa7RjzXZMlFGFBZg+HbGwV 9+qQ== ARC-Authentication-Results: i=1; mx.google.com; spf=softfail (google.com: domain of transitioning gregkh@linuxfoundation.org does not designate 90.92.71.90 as permitted sender) smtp.mailfrom=gregkh@linuxfoundation.org Authentication-Results: mx.google.com; spf=softfail (google.com: domain of transitioning gregkh@linuxfoundation.org does not designate 90.92.71.90 as permitted sender) smtp.mailfrom=gregkh@linuxfoundation.org From: Greg Kroah-Hartman To: linux-kernel@vger.kernel.org Cc: Greg Kroah-Hartman , stable@vger.kernel.org, Max Filippov Subject: [PATCH 4.9 75/88] xtensa: fix futex_atomic_cmpxchg_inatomic Date: Thu, 15 Feb 2018 16:17:42 +0100 Message-Id: <20180215151232.895236769@linuxfoundation.org> X-Mailer: git-send-email 2.16.1 In-Reply-To: <20180215151222.437136975@linuxfoundation.org> References: <20180215151222.437136975@linuxfoundation.org> User-Agent: quilt/0.65 MIME-Version: 1.0 Content-Type: text/plain; charset=UTF-8 X-getmail-retrieved-from-mailbox: INBOX X-GMAIL-LABELS: =?utf-8?b?IlxcU2VudCI=?= X-GMAIL-THRID: =?utf-8?q?1592480769217450134?= X-GMAIL-MSGID: =?utf-8?q?1592481314148546601?= X-Mailing-List: linux-kernel@vger.kernel.org List-ID: 4.9-stable review patch. If anyone has any objections, please let me know. ------------------ From: Max Filippov commit ca47480921587ae30417dd234a9f79af188e3666 upstream. Return 0 if the operation was successful, not the userspace memory value. Check that userspace value equals passed oldval, not itself. Don't update *uval if the value wasn't read from userspace memory. This fixes process hang due to infinite loop in futex_lock_pi. It also fixes a bunch of glibc tests nptl/tst-mutexpi*. Signed-off-by: Max Filippov Signed-off-by: Greg Kroah-Hartman --- arch/xtensa/include/asm/futex.h | 23 ++++++++++------------- 1 file changed, 10 insertions(+), 13 deletions(-) --- a/arch/xtensa/include/asm/futex.h +++ b/arch/xtensa/include/asm/futex.h @@ -109,7 +109,6 @@ futex_atomic_cmpxchg_inatomic(u32 *uval, u32 oldval, u32 newval) { int ret = 0; - u32 prev; if (!access_ok(VERIFY_WRITE, uaddr, sizeof(u32))) return -EFAULT; @@ -120,26 +119,24 @@ futex_atomic_cmpxchg_inatomic(u32 *uval, __asm__ __volatile__ ( " # futex_atomic_cmpxchg_inatomic\n" - "1: l32i %1, %3, 0\n" - " mov %0, %5\n" - " wsr %1, scompare1\n" - "2: s32c1i %0, %3, 0\n" - "3:\n" + " wsr %5, scompare1\n" + "1: s32c1i %1, %4, 0\n" + " s32i %1, %6, 0\n" + "2:\n" " .section .fixup,\"ax\"\n" " .align 4\n" - "4: .long 3b\n" - "5: l32r %1, 4b\n" - " movi %0, %6\n" + "3: .long 2b\n" + "4: l32r %1, 3b\n" + " movi %0, %7\n" " jx %1\n" " .previous\n" " .section __ex_table,\"a\"\n" - " .long 1b,5b,2b,5b\n" + " .long 1b,4b\n" " .previous\n" - : "+r" (ret), "=&r" (prev), "+m" (*uaddr) - : "r" (uaddr), "r" (oldval), "r" (newval), "I" (-EFAULT) + : "+r" (ret), "+r" (newval), "+m" (*uaddr), "+m" (*uval) + : "r" (uaddr), "r" (oldval), "r" (uval), "I" (-EFAULT) : "memory"); - *uval = prev; return ret; }