Hi Julia,
I am afraid I do not understand your question. This is how the code is
supposed to work:
An SMC-R connection is allowed to run with one of 16 discrete possible
buffer sizes and requires contiguous memory for this buffer. If there is
no buffer available that can be reused (from a previous SMC-R
connection), a new one is allocated. If allocation fails, the code
"continues" and reduces the desired buffer size to the next smaller
buffer size, and tries to reuse or allocate memory of this size.
"continue" stops, if the lowest possible value has been tried without
success. In this case tmp_bufsize_short is negative and -ENOMEM is returned.
On 08/09/2016 02:09 PM, Julia Lawall wrote:
Is there a guarantee that the contrinues can't fall off the end of the
loop?
julia
---------- Forwarded message ----------
Date: Tue, 9 Aug 2016 20:06:24 +0800
From: kbuild test robot <fengguang...@intel.com>
To: kbu...@01.org
Cc: Julia Lawall <julia.law...@lip6.fr>
Subject: Re: [PATCH RESEND net-next 07/15] smc: remote memory buffers (RMBs)
CC: kbuild-...@01.org
In-Reply-To: <1470737580-43012-8-git-send-email-ubr...@linux.vnet.ibm.com>
TO: Ursula Braun <ubr...@linux.vnet.ibm.com>
CC: da...@davemloft.net
CC: netdev@vger.kernel.org, linux-s...@vger.kernel.org, schwidef...@de.ibm.com,
heiko.carst...@de.ibm.com, utz.bac...@de.ibm.com, ubr...@linux.vnet.ibm.com
Hi Ursula,
[auto build test WARNING on net-next/master]
url:
https://github.com/0day-ci/linux/commits/Ursula-Braun/net-smc-Shared-Memory-Communications-RDMA/20160809-182526
:::::: branch date: 2 hours ago
:::::: commit date: 2 hours ago
net/smc/smc_core.c:570:17-25: ERROR: reference preceded by free on line 549
net/smc/smc_core.c:570:17-25: ERROR: reference preceded by free on line 560
net/smc/smc_core.c:507:20-31: ERROR: reference preceded by free on line 486
net/smc/smc_core.c:507:20-31: ERROR: reference preceded by free on line 497
git remote add linux-review https://github.com/0day-ci/linux
git remote update linux-review
git checkout 2e8eda2734f14a860721121549f05e5ecd13d81d
vim +570 net/smc/smc_core.c
2e8eda27 Ursula Braun 2016-08-09 543 break; /* give up with
-ENOMEM */
2e8eda27 Ursula Braun 2016-08-09 544 rmb_desc->cpu_addr =
kzalloc(tmp_bufsize,
2e8eda27 Ursula Braun 2016-08-09 545
GFP_KERNEL | __GFP_NOWARN |
2e8eda27 Ursula Braun 2016-08-09 546
__GFP_NOMEMALLOC |
2e8eda27 Ursula Braun 2016-08-09 547
__GFP_NORETRY);
2e8eda27 Ursula Braun 2016-08-09 548 if (!rmb_desc->cpu_addr) {
2e8eda27 Ursula Braun 2016-08-09 @549 kfree(rmb_desc);
2e8eda27 Ursula Braun 2016-08-09 550 /* if RMB allocation
has failed,
2e8eda27 Ursula Braun 2016-08-09 551 * try a smaller one
2e8eda27 Ursula Braun 2016-08-09 552 */
2e8eda27 Ursula Braun 2016-08-09 553 continue;
2e8eda27 Ursula Braun 2016-08-09 554 }
2e8eda27 Ursula Braun 2016-08-09 555 rc =
smc_ib_buf_map(lgr->lnk[SMC_SINGLE_LINK].smcibdev,
2e8eda27 Ursula Braun 2016-08-09 556
tmp_bufsize, rmb_desc,
2e8eda27 Ursula Braun 2016-08-09 557
DMA_FROM_DEVICE);
2e8eda27 Ursula Braun 2016-08-09 558 if (rc) {
2e8eda27 Ursula Braun 2016-08-09 559
kfree(rmb_desc->cpu_addr);
2e8eda27 Ursula Braun 2016-08-09 560 kfree(rmb_desc);
2e8eda27 Ursula Braun 2016-08-09 561 continue; /* if mapping
failed, try smaller one */
2e8eda27 Ursula Braun 2016-08-09 562 }
2e8eda27 Ursula Braun 2016-08-09 563 rmb_desc->used = 1;
2e8eda27 Ursula Braun 2016-08-09 564 write_lock_bh(&lgr->rmbs_lock);
2e8eda27 Ursula Braun 2016-08-09 565 list_add(&rmb_desc->list,
2e8eda27 Ursula Braun 2016-08-09 566
&lgr->rmbs[tmp_bufsize_short]);
2e8eda27 Ursula Braun 2016-08-09 567
write_unlock_bh(&lgr->rmbs_lock);
2e8eda27 Ursula Braun 2016-08-09 568 break;
2e8eda27 Ursula Braun 2016-08-09 569 }
2e8eda27 Ursula Braun 2016-08-09 @570 if (rmb_desc && rmb_desc->cpu_addr) {
2e8eda27 Ursula Braun 2016-08-09 571 conn->rmb_desc = rmb_desc;
2e8eda27 Ursula Braun 2016-08-09 572 conn->rmbe_size = tmp_bufsize;
2e8eda27 Ursula Braun 2016-08-09 573 conn->rmbe_size_short =
tmp_bufsize_short;
---
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