From mboxrd@z Thu Jan 1 00:00:00 1970 From: Julia Lawall Subject: Re: [PATCH v26 12/12] LRNG - add interface for gathering of raw entropy (fwd) Date: Tue, 26 Nov 2019 19:04:10 +0100 (CET) Message-ID: Mime-Version: 1.0 Content-Type: multipart/mixed; boundary="8323329-739979723-1574791451=:2605" Return-path: Sender: linux-kernel-owner@vger.kernel.org To: =?ISO-8859-15?Q?Stephan_M=FCller?= Cc: Greg Kroah-Hartman , linux-crypto@vger.kernel.org, LKML , linux-api@vger.kernel.org, "Eric W. Biederman" , "Alexander E. Patrakov" , "Ahmed S. Darwish" , "Theodore Y. Ts'o" , Willy Tarreau , Matthew Garrett , Vito Caputo , Andreas Dilger , Jan Kara , Ray Strode , William Jon McCann , zhangjs , Andy Lutomirski , Florian Weimer , Lennart Poettering , Nicolai Stange , "Peter, Matthias" List-Id: linux-api@vger.kernel.org This message is in MIME format. The first part should be readable text, while the remaining parts are likely unreadable without MIME-aware tools. --8323329-739979723-1574791451=:2605 Content-Type: text/plain; charset=iso-8859-1 Content-Transfer-Encoding: 8BIT Hello, Should something be done about the lock on line 162? julia ---------- Forwarded message ---------- Date: Tue, 26 Nov 2019 01:12:49 +0800 From: kbuild test robot To: kbuild@lists.01.org Cc: Julia Lawall Subject: Re: [PATCH v26 12/12] LRNG - add interface for gathering of raw entropy In-Reply-To: <3742813.K7GG538zxB@positron.chronox.de> References: <3742813.K7GG538zxB@positron.chronox.de> Hi "Stephan, Thank you for the patch! Perhaps something to improve: [auto build test WARNING on char-misc/char-misc-testing] [also build test WARNING on v5.4 next-20191125] [if your patch is applied to the wrong git tree, please drop us a note to help improve the system. BTW, we also suggest to use '--base' option to specify the base tree in git format-patch, please see https://stackoverflow.com/a/37406982] url: https://github.com/0day-ci/linux/commits/Stephan-M-ller/dev-random-a-new-approach-with-full-SP800-90B/20191125-042152 base: https://git.kernel.org/pub/scm/linux/kernel/git/gregkh/char-misc.git b78cda795ac83333293f1bfa3165572a47e550c2 :::::: branch date: 21 hours ago :::::: commit date: 21 hours ago If you fix the issue, kindly add following tag Reported-by: kbuild test robot Reported-by: Julia Lawall >> drivers/char/lrng/lrng_testing.c:176:1-7: preceding lock on line 134 # https://github.com/0day-ci/linux/commit/d69edb724ef2677392bfcbaf4fb6750306f8a1f1 git remote add linux-review https://github.com/0day-ci/linux git remote update linux-review git checkout d69edb724ef2677392bfcbaf4fb6750306f8a1f1 vim +176 drivers/char/lrng/lrng_testing.c d69edb724ef267 Stephan Müller 2019-11-23 125 d69edb724ef267 Stephan Müller 2019-11-23 126 static int lrng_raw_entropy_reader(u8 *outbuf, u32 outbuflen) d69edb724ef267 Stephan Müller 2019-11-23 127 { d69edb724ef267 Stephan Müller 2019-11-23 128 unsigned long flags; d69edb724ef267 Stephan Müller 2019-11-23 129 int collected_data = 0; d69edb724ef267 Stephan Müller 2019-11-23 130 d69edb724ef267 Stephan Müller 2019-11-23 131 lrng_raw_entropy_init(); d69edb724ef267 Stephan Müller 2019-11-23 132 d69edb724ef267 Stephan Müller 2019-11-23 133 while (outbuflen) { d69edb724ef267 Stephan Müller 2019-11-23 @134 spin_lock_irqsave(&lrng_raw_lock, flags); d69edb724ef267 Stephan Müller 2019-11-23 135 d69edb724ef267 Stephan Müller 2019-11-23 136 /* We have no data or reached the writer. */ d69edb724ef267 Stephan Müller 2019-11-23 137 if (!lrng_rb_writer || (lrng_rb_writer == lrng_rb_reader)) { d69edb724ef267 Stephan Müller 2019-11-23 138 d69edb724ef267 Stephan Müller 2019-11-23 139 spin_unlock_irqrestore(&lrng_raw_lock, flags); d69edb724ef267 Stephan Müller 2019-11-23 140 d69edb724ef267 Stephan Müller 2019-11-23 141 /* d69edb724ef267 Stephan Müller 2019-11-23 142 * Now we gathered all boot data, enable regular data d69edb724ef267 Stephan Müller 2019-11-23 143 * collection. d69edb724ef267 Stephan Müller 2019-11-23 144 */ d69edb724ef267 Stephan Müller 2019-11-23 145 if (boot_test) { d69edb724ef267 Stephan Müller 2019-11-23 146 boot_test = 0; d69edb724ef267 Stephan Müller 2019-11-23 147 goto out; d69edb724ef267 Stephan Müller 2019-11-23 148 } d69edb724ef267 Stephan Müller 2019-11-23 149 d69edb724ef267 Stephan Müller 2019-11-23 150 wait_event_interruptible(lrng_raw_read_wait, d69edb724ef267 Stephan Müller 2019-11-23 151 lrng_raw_have_data()); d69edb724ef267 Stephan Müller 2019-11-23 152 if (signal_pending(current)) { d69edb724ef267 Stephan Müller 2019-11-23 153 collected_data = -ERESTARTSYS; d69edb724ef267 Stephan Müller 2019-11-23 154 goto out; d69edb724ef267 Stephan Müller 2019-11-23 155 } d69edb724ef267 Stephan Müller 2019-11-23 156 d69edb724ef267 Stephan Müller 2019-11-23 157 continue; d69edb724ef267 Stephan Müller 2019-11-23 158 } d69edb724ef267 Stephan Müller 2019-11-23 159 d69edb724ef267 Stephan Müller 2019-11-23 160 /* We copy out word-wise */ d69edb724ef267 Stephan Müller 2019-11-23 161 if (outbuflen < sizeof(u32)) d69edb724ef267 Stephan Müller 2019-11-23 162 goto out; d69edb724ef267 Stephan Müller 2019-11-23 163 d69edb724ef267 Stephan Müller 2019-11-23 164 memcpy(outbuf, &lrng_testing_rb[lrng_rb_reader], sizeof(u32)); d69edb724ef267 Stephan Müller 2019-11-23 165 lrng_rb_reader++; d69edb724ef267 Stephan Müller 2019-11-23 166 d69edb724ef267 Stephan Müller 2019-11-23 167 spin_unlock_irqrestore(&lrng_raw_lock, flags); d69edb724ef267 Stephan Müller 2019-11-23 168 d69edb724ef267 Stephan Müller 2019-11-23 169 outbuf += sizeof(u32); d69edb724ef267 Stephan Müller 2019-11-23 170 outbuflen -= sizeof(u32); d69edb724ef267 Stephan Müller 2019-11-23 171 collected_data += sizeof(u32); d69edb724ef267 Stephan Müller 2019-11-23 172 } d69edb724ef267 Stephan Müller 2019-11-23 173 d69edb724ef267 Stephan Müller 2019-11-23 174 out: d69edb724ef267 Stephan Müller 2019-11-23 175 lrng_raw_entropy_fini(); d69edb724ef267 Stephan Müller 2019-11-23 @176 return collected_data; d69edb724ef267 Stephan Müller 2019-11-23 177 } d69edb724ef267 Stephan Müller 2019-11-23 178 --- 0-DAY kernel test infrastructure Open Source Technology Center https://lists.01.org/hyperkitty/list/kbuild-all@lists.01.org Intel Corporation --8323329-739979723-1574791451=:2605--