Re: [PATCH 3/3] NTB: Add flush_req and wakeup interface

From: kbuild test robot
Date: Thu Dec 17 2015 - 06:30:52 EST


Hi Xiangliang,

[auto build test WARNING on v4.4-rc5]
[also build test WARNING on next-20151217]

url: https://github.com/0day-ci/linux/commits/Xiangliang-Yu/NTB-Add-AMD-PCI-Express-NTB-driver/20151217-113608
config: x86_64-randconfig-n0-12171710 (attached as .config)
reproduce:
# save the attached .config to linux build tree
make ARCH=x86_64

Note: it may well be a FALSE warning. FWIW you are at least aware of it now.
http://gcc.gnu.org/wiki/Better_Uninitialized_Warnings

All warnings (new ones prefixed by >>):

drivers/ntb/hw/amd/ntb_hw_amd.c: In function 'amd_ntb_mw_set_trans':
drivers/ntb/hw/amd/ntb_hw_amd.c:189:6: warning: 'limit' may be used uninitialized in this function [-Wmaybe-uninitialized]
if (reg_val != limit) {
^
drivers/ntb/hw/amd/ntb_hw_amd.c: In function 'amd_ntb_wakeup_peer_side':
>> drivers/ntb/hw/amd/ntb_hw_amd.c:526:6: warning: 'reg' may be used uninitialized in this function [-Wmaybe-uninitialized]
reg |= 0x1;
^
drivers/ntb/hw/amd/ntb_hw_amd.c:518:6: note: 'reg' was declared here
u32 reg;
^

vim +/reg +526 drivers/ntb/hw/amd/ntb_hw_amd.c

58a6d117 Xiangliang Yu 2015-12-17 510 return amd_flush_peer_requests(ndev);
58a6d117 Xiangliang Yu 2015-12-17 511 }
58a6d117 Xiangliang Yu 2015-12-17 512
a635755a Xiangliang Yu 2015-12-17 513 /*
a635755a Xiangliang Yu 2015-12-17 514 * wake up the peer side
a635755a Xiangliang Yu 2015-12-17 515 */
a635755a Xiangliang Yu 2015-12-17 516 static int amd_wakeup_peer_side(struct amd_ntb_dev *ndev)
a635755a Xiangliang Yu 2015-12-17 517 {
a635755a Xiangliang Yu 2015-12-17 518 u32 reg;
a635755a Xiangliang Yu 2015-12-17 519
a635755a Xiangliang Yu 2015-12-17 520 if (!amd_link_is_up(ndev)) {
a635755a Xiangliang Yu 2015-12-17 521 dev_warn(ndev_dev(ndev), "link is down.\n");
a635755a Xiangliang Yu 2015-12-17 522 return -EINVAL;
a635755a Xiangliang Yu 2015-12-17 523 }
a635755a Xiangliang Yu 2015-12-17 524
a635755a Xiangliang Yu 2015-12-17 525 NTB_READ_REG(PMSGTRIG);
a635755a Xiangliang Yu 2015-12-17 @526 reg |= 0x1;
a635755a Xiangliang Yu 2015-12-17 527 NTB_WRITE_REG(reg, PMSGTRIG);
a635755a Xiangliang Yu 2015-12-17 528
a635755a Xiangliang Yu 2015-12-17 529 wait_for_completion(&ndev->wakeup_cmpl);
a635755a Xiangliang Yu 2015-12-17 530
a635755a Xiangliang Yu 2015-12-17 531 return 0;
a635755a Xiangliang Yu 2015-12-17 532 }
a635755a Xiangliang Yu 2015-12-17 533
58a6d117 Xiangliang Yu 2015-12-17 534 static int amd_ntb_wakeup_peer_side(struct ntb_dev *ntb)

:::::: The code at line 526 was first introduced by commit
:::::: a635755a710138a6f505cc7e62693741786fb19e NTB: Add AMD PCI-Express NTB driver

:::::: TO: Xiangliang Yu <Xiangliang.Yu@xxxxxxx>
:::::: CC: 0day robot <fengguang.wu@xxxxxxxxx>

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