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* [tip:x86/urgent] BUILD SUCCESS WITH WARNING 064855a69003c24bd6b473b367d364e418c57625
@ 2021-08-15  8:36 kernel test robot
  2021-08-15  8:42 ` Borislav Petkov
  0 siblings, 1 reply; 9+ messages in thread
From: kernel test robot @ 2021-08-15  8:36 UTC (permalink / raw)
  To: x86-ml; +Cc: linux-kernel

tree/branch: https://git.kernel.org/pub/scm/linux/kernel/git/tip/tip.git x86/urgent
branch HEAD: 064855a69003c24bd6b473b367d364e418c57625  x86/resctrl: Fix default monitoring groups reporting

possible Warning in current branch:

arch/x86/kernel/cpu/resctrl/monitor.c:310 __mon_event_count() error: uninitialized symbol 'm'.
arch/x86/kernel/cpu/resctrl/monitor.c:315 __mon_event_count() error: potentially dereferencing uninitialized 'm'.

Warning ids grouped by kconfigs:

gcc_recent_errors
`-- i386-randconfig-m021-20210812
    |-- arch-x86-kernel-cpu-resctrl-monitor.c-__mon_event_count()-error:potentially-dereferencing-uninitialized-m-.
    `-- arch-x86-kernel-cpu-resctrl-monitor.c-__mon_event_count()-error:uninitialized-symbol-m-.

elapsed time: 3699m

configs tested: 236
configs skipped: 69

gcc tested configs:
arm                                 defconfig
arm64                            allyesconfig
arm64                               defconfig
arm                              allyesconfig
arm                              allmodconfig
i386                 randconfig-c001-20210814
i386                 randconfig-c001-20210812
i386                 randconfig-c001-20210813
powerpc                     tqm8541_defconfig
m68k                          amiga_defconfig
mips                        bcm47xx_defconfig
xtensa                           alldefconfig
sh                              ul2_defconfig
powerpc                 mpc8540_ads_defconfig
ia64                                defconfig
arm                       imx_v6_v7_defconfig
mips                           rs90_defconfig
parisc                generic-32bit_defconfig
arm                     am200epdkit_defconfig
openrisc                  or1klitex_defconfig
m68k                        m5407c3_defconfig
powerpc                    klondike_defconfig
mips                     loongson1c_defconfig
arm                          ep93xx_defconfig
arm                          iop32x_defconfig
mips                  maltasmvp_eva_defconfig
mips                         bigsur_defconfig
powerpc64                           defconfig
powerpc                        cell_defconfig
arm                     davinci_all_defconfig
mips                        workpad_defconfig
arm                       omap2plus_defconfig
powerpc                     pq2fads_defconfig
h8300                            alldefconfig
mips                  cavium_octeon_defconfig
nds32                               defconfig
parisc                           alldefconfig
arm                      tct_hammer_defconfig
powerpc                      obs600_defconfig
powerpc                      makalu_defconfig
powerpc                     tqm5200_defconfig
powerpc                      walnut_defconfig
mips                      bmips_stb_defconfig
sh                           se7619_defconfig
arm                         orion5x_defconfig
arm                         shannon_defconfig
arm                        clps711x_defconfig
powerpc                      ppc64e_defconfig
xtensa                           allyesconfig
arm                       imx_v4_v5_defconfig
powerpc                      ep88xc_defconfig
powerpc                     rainier_defconfig
sh                            shmin_defconfig
h8300                               defconfig
powerpc               mpc834x_itxgp_defconfig
mips                        maltaup_defconfig
mips                           ip22_defconfig
sh                           se7721_defconfig
sh                          rsk7269_defconfig
ia64                          tiger_defconfig
arm                             rpc_defconfig
powerpc                      ppc40x_defconfig
arm                          simpad_defconfig
powerpc                      ppc6xx_defconfig
powerpc                 mpc837x_mds_defconfig
ia64                             alldefconfig
sh                        edosk7705_defconfig
sh                           se7750_defconfig
powerpc                    socrates_defconfig
riscv                             allnoconfig
powerpc                     ksi8560_defconfig
powerpc                 mpc837x_rdb_defconfig
powerpc                       maple_defconfig
powerpc                         wii_defconfig
h8300                            allyesconfig
h8300                       h8s-sim_defconfig
arm                       aspeed_g4_defconfig
sh                  sh7785lcr_32bit_defconfig
mips                       lemote2f_defconfig
mips                          rm200_defconfig
arm                           stm32_defconfig
powerpc                       ppc64_defconfig
xtensa                  audio_kc705_defconfig
mips                      loongson3_defconfig
mips                          ath79_defconfig
arc                     haps_hs_smp_defconfig
sh                           se7712_defconfig
powerpc                   microwatt_defconfig
sh                          urquell_defconfig
mips                     decstation_defconfig
arm                          exynos_defconfig
sh                          r7780mp_defconfig
arm                       cns3420vb_defconfig
mips                          ath25_defconfig
m68k                             allyesconfig
powerpc                    amigaone_defconfig
arm                         s5pv210_defconfig
arm                           viper_defconfig
sh                          lboxre2_defconfig
powerpc                     redwood_defconfig
mips                         tb0226_defconfig
arm                      jornada720_defconfig
mips                           ip27_defconfig
m68k                       bvme6000_defconfig
mips                     cu1830-neo_defconfig
powerpc                     asp8347_defconfig
xtensa                          iss_defconfig
powerpc                 canyonlands_defconfig
microblaze                      mmu_defconfig
arm                         nhk8815_defconfig
powerpc                     powernv_defconfig
arm                        magician_defconfig
powerpc                       eiger_defconfig
ia64                         bigsur_defconfig
powerpc64                        alldefconfig
powerpc                    ge_imp3a_defconfig
xtensa                         virt_defconfig
arm                            mmp2_defconfig
m68k                        mvme147_defconfig
openrisc                 simple_smp_defconfig
x86_64                            allnoconfig
ia64                             allmodconfig
ia64                             allyesconfig
m68k                             allmodconfig
m68k                                defconfig
nios2                               defconfig
arc                              allyesconfig
nds32                             allnoconfig
nios2                            allyesconfig
csky                                defconfig
alpha                               defconfig
alpha                            allyesconfig
arc                                 defconfig
sh                               allmodconfig
parisc                              defconfig
s390                             allyesconfig
s390                             allmodconfig
parisc                           allyesconfig
s390                                defconfig
i386                             allyesconfig
sparc                            allyesconfig
sparc                               defconfig
i386                                defconfig
mips                             allyesconfig
mips                             allmodconfig
powerpc                          allyesconfig
powerpc                          allmodconfig
powerpc                           allnoconfig
x86_64               randconfig-a004-20210814
x86_64               randconfig-a006-20210814
x86_64               randconfig-a003-20210814
x86_64               randconfig-a001-20210814
x86_64               randconfig-a005-20210814
x86_64               randconfig-a002-20210814
x86_64               randconfig-a006-20210812
x86_64               randconfig-a004-20210812
x86_64               randconfig-a003-20210812
x86_64               randconfig-a005-20210812
x86_64               randconfig-a002-20210812
x86_64               randconfig-a001-20210812
i386                 randconfig-a004-20210812
i386                 randconfig-a003-20210812
i386                 randconfig-a002-20210812
i386                 randconfig-a001-20210812
i386                 randconfig-a006-20210812
i386                 randconfig-a005-20210812
i386                 randconfig-a004-20210814
i386                 randconfig-a002-20210814
i386                 randconfig-a001-20210814
i386                 randconfig-a003-20210814
i386                 randconfig-a006-20210814
i386                 randconfig-a005-20210814
i386                 randconfig-a004-20210813
i386                 randconfig-a003-20210813
i386                 randconfig-a001-20210813
i386                 randconfig-a002-20210813
i386                 randconfig-a006-20210813
i386                 randconfig-a005-20210813
x86_64               randconfig-a011-20210813
x86_64               randconfig-a013-20210813
x86_64               randconfig-a012-20210813
x86_64               randconfig-a016-20210813
x86_64               randconfig-a015-20210813
x86_64               randconfig-a014-20210813
i386                 randconfig-a011-20210814
i386                 randconfig-a015-20210814
i386                 randconfig-a013-20210814
i386                 randconfig-a014-20210814
i386                 randconfig-a016-20210814
i386                 randconfig-a012-20210814
i386                 randconfig-a011-20210812
i386                 randconfig-a015-20210812
i386                 randconfig-a013-20210812
i386                 randconfig-a014-20210812
i386                 randconfig-a016-20210812
i386                 randconfig-a012-20210812
i386                 randconfig-a011-20210813
i386                 randconfig-a015-20210813
i386                 randconfig-a014-20210813
i386                 randconfig-a013-20210813
i386                 randconfig-a016-20210813
i386                 randconfig-a012-20210813
riscv                    nommu_k210_defconfig
riscv                            allyesconfig
riscv                    nommu_virt_defconfig
riscv                               defconfig
riscv                          rv32_defconfig
riscv                            allmodconfig
x86_64                    rhel-8.3-kselftests
um                           x86_64_defconfig
um                             i386_defconfig
x86_64                           allyesconfig
x86_64                              defconfig
x86_64                               rhel-8.3
x86_64                                  kexec

clang tested configs:
x86_64               randconfig-c001-20210812
x86_64               randconfig-c001-20210813
x86_64               randconfig-c001-20210814
x86_64               randconfig-a006-20210813
x86_64               randconfig-a004-20210813
x86_64               randconfig-a003-20210813
x86_64               randconfig-a002-20210813
x86_64               randconfig-a005-20210813
x86_64               randconfig-a001-20210813
x86_64               randconfig-a011-20210812
x86_64               randconfig-a013-20210812
x86_64               randconfig-a012-20210812
x86_64               randconfig-a016-20210812
x86_64               randconfig-a015-20210812
x86_64               randconfig-a014-20210812
x86_64               randconfig-a013-20210814
x86_64               randconfig-a011-20210814
x86_64               randconfig-a016-20210814
x86_64               randconfig-a012-20210814
x86_64               randconfig-a014-20210814
x86_64               randconfig-a015-20210814

---
0-DAY CI Kernel Test Service, Intel Corporation
https://lists.01.org/hyperkitty/list/kbuild-all@lists.01.org

^ permalink raw reply	[flat|nested] 9+ messages in thread

* Re: [tip:x86/urgent] BUILD SUCCESS WITH WARNING 064855a69003c24bd6b473b367d364e418c57625
  2021-08-15  8:36 [tip:x86/urgent] BUILD SUCCESS WITH WARNING 064855a69003c24bd6b473b367d364e418c57625 kernel test robot
@ 2021-08-15  8:42 ` Borislav Petkov
  2021-08-15 10:22   ` Philip Li
  2021-08-19  6:15   ` Chen, Rong A
  0 siblings, 2 replies; 9+ messages in thread
From: Borislav Petkov @ 2021-08-15  8:42 UTC (permalink / raw)
  To: kernel test robot; +Cc: x86-ml, linux-kernel

Hi,

On Sun, Aug 15, 2021 at 04:36:40PM +0800, kernel test robot wrote:
> tree/branch: https://git.kernel.org/pub/scm/linux/kernel/git/tip/tip.git x86/urgent
> branch HEAD: 064855a69003c24bd6b473b367d364e418c57625  x86/resctrl: Fix default monitoring groups reporting
> 
> possible Warning in current branch:
> 
> arch/x86/kernel/cpu/resctrl/monitor.c:310 __mon_event_count() error: uninitialized symbol 'm'.
> arch/x86/kernel/cpu/resctrl/monitor.c:315 __mon_event_count() error: potentially dereferencing uninitialized 'm'.
> 
> Warning ids grouped by kconfigs:
> 
> gcc_recent_errors
> `-- i386-randconfig-m021-20210812
>     |-- arch-x86-kernel-cpu-resctrl-monitor.c-__mon_event_count()-error:potentially-dereferencing-uninitialized-m-.
>     `-- arch-x86-kernel-cpu-resctrl-monitor.c-__mon_event_count()-error:uninitialized-symbol-m-.

AFAIR, I had already asked you guys to make those reports more useful
as, for example, adding a link to that randconfig above or even
attaching it so that a person - not a machine - reading it, can
*actually* act upon it.

But that hasn't happened.

Until it happens, I'm going to ignore all those reports from you.

-- 
Regards/Gruss,
    Boris.

https://people.kernel.org/tglx/notes-about-netiquette

^ permalink raw reply	[flat|nested] 9+ messages in thread

* Re: [tip:x86/urgent] BUILD SUCCESS WITH WARNING 064855a69003c24bd6b473b367d364e418c57625
  2021-08-15  8:42 ` Borislav Petkov
@ 2021-08-15 10:22   ` Philip Li
  2021-08-19  6:15   ` Chen, Rong A
  1 sibling, 0 replies; 9+ messages in thread
From: Philip Li @ 2021-08-15 10:22 UTC (permalink / raw)
  To: Borislav Petkov; +Cc: kernel test robot, x86-ml, linux-kernel

On Sun, Aug 15, 2021 at 10:42:58AM +0200, Borislav Petkov wrote:
> Hi,
> 
> On Sun, Aug 15, 2021 at 04:36:40PM +0800, kernel test robot wrote:
> > tree/branch: https://git.kernel.org/pub/scm/linux/kernel/git/tip/tip.git x86/urgent
> > branch HEAD: 064855a69003c24bd6b473b367d364e418c57625  x86/resctrl: Fix default monitoring groups reporting
> > 
> > possible Warning in current branch:
> > 
> > arch/x86/kernel/cpu/resctrl/monitor.c:310 __mon_event_count() error: uninitialized symbol 'm'.
> > arch/x86/kernel/cpu/resctrl/monitor.c:315 __mon_event_count() error: potentially dereferencing uninitialized 'm'.
> > 
> > Warning ids grouped by kconfigs:
> > 
> > gcc_recent_errors
> > `-- i386-randconfig-m021-20210812
> >     |-- arch-x86-kernel-cpu-resctrl-monitor.c-__mon_event_count()-error:potentially-dereferencing-uninitialized-m-.
> >     `-- arch-x86-kernel-cpu-resctrl-monitor.c-__mon_event_count()-error:uninitialized-symbol-m-.
> 
> AFAIR, I had already asked you guys to make those reports more useful
> as, for example, adding a link to that randconfig above or even
> attaching it so that a person - not a machine - reading it, can
> *actually* act upon it.
> 
> But that hasn't happened.
Sorry Boris, we actually followed this suggestion to enable such logic, and
it is supposed to show the report link like below in the summary report in case
the user doesn't receive the standalone issue report.

We will check what happened here and look for resolving it soon.

	tree/branch: https://git.kernel.org/pub/scm/linux/kernel/git/mcgrof/linux-next.git 20210813-sysfs-fixes-v8
	branch HEAD: f5b8aadeca76656caad8bccc795bfe7b0730230a  zram: use ATTRIBUTE_GROUPS to fix sysfs deadlock module removal

	Error/Warning reports:

	https://lore.kernel.org/lkml/202108141020.SK0WVBMv-lkp@intel.com
	https://lore.kernel.org/lkml/202108141131.dFBzZxp1-lkp@intel.com
	https://lore.kernel.org/lkml/202108141238.Ch3EsLWk-lkp@intel.com
	https://lore.kernel.org/lkml/202108141311.9xkkGVte-lkp@intel.com
	https://lore.kernel.org/lkml/202108142031.4ZMZDpLa-lkp@intel.com
	https://lore.kernel.org/lkml/202108142340.phk6ixfR-lkp@intel.com

	Error/Warning in current branch:

	arch/x86/kernel/cpu/resctrl/rdtgroup.c:210:7: error: too few arguments to function '__kernfs_create_file'
	arch/x86/kernel/cpu/resctrl/rdtgroup.c:212:13: warning: passing argument 7 of '__kernfs_create_file' makes integer from pointer without a cast [-Wint-conversion]
	arch/x86/kernel/cpu/resctrl/rdtgroup.c:212:23: error: passing argument 8 of '__kernfs_create_file' from incompatible pointer type [-Werror=incompatible-pointer-types]
	arch/x86/kernel/cpu/resctrl/rdtgroup.c:212:38: error: too few arguments to function call, expected 11, have 10

Thanks

> 
> Until it happens, I'm going to ignore all those reports from you.
> 
> -- 
> Regards/Gruss,
>     Boris.
> 
> https://people.kernel.org/tglx/notes-about-netiquette

^ permalink raw reply	[flat|nested] 9+ messages in thread

* Re: [tip:x86/urgent] BUILD SUCCESS WITH WARNING 064855a69003c24bd6b473b367d364e418c57625
  2021-08-15  8:42 ` Borislav Petkov
  2021-08-15 10:22   ` Philip Li
@ 2021-08-19  6:15   ` Chen, Rong A
  2021-08-19  9:00     ` Borislav Petkov
  1 sibling, 1 reply; 9+ messages in thread
From: Chen, Rong A @ 2021-08-19  6:15 UTC (permalink / raw)
  To: Borislav Petkov, kernel test robot; +Cc: x86-ml, linux-kernel



On 8/15/2021 4:42 PM, Borislav Petkov wrote:
> Hi,
> 
> On Sun, Aug 15, 2021 at 04:36:40PM +0800, kernel test robot wrote:
>> tree/branch: https://git.kernel.org/pub/scm/linux/kernel/git/tip/tip.git x86/urgent
>> branch HEAD: 064855a69003c24bd6b473b367d364e418c57625  x86/resctrl: Fix default monitoring groups reporting
>>
>> possible Warning in current branch:
>>
>> arch/x86/kernel/cpu/resctrl/monitor.c:310 __mon_event_count() error: uninitialized symbol 'm'.
>> arch/x86/kernel/cpu/resctrl/monitor.c:315 __mon_event_count() error: potentially dereferencing uninitialized 'm'.
>>
>> Warning ids grouped by kconfigs:
>>
>> gcc_recent_errors
>> `-- i386-randconfig-m021-20210812
>>      |-- arch-x86-kernel-cpu-resctrl-monitor.c-__mon_event_count()-error:potentially-dereferencing-uninitialized-m-.
>>      `-- arch-x86-kernel-cpu-resctrl-monitor.c-__mon_event_count()-error:uninitialized-symbol-m-.
> 
> AFAIR, I had already asked you guys to make those reports more useful
> as, for example, adding a link to that randconfig above or even
> attaching it so that a person - not a machine - reading it, can
> *actually* act upon it.
> 
> But that hasn't happened.
> 
> Until it happens, I'm going to ignore all those reports from you.
> 

Hi Borislav,

Sorry about it, the actual link is at 
https://lists.01.org/hyperkitty/list/kbuild@lists.01.org/thread/PZVMY3VJU4QY4HQXHK3MLPQ2KZ5CNAYH/,
and it's still an internal report that the robot don't know whether it's 
a false positive or not, we'll update the mail contents to avoid 
misunderstanding.

Best Regards,
Rong Chen

^ permalink raw reply	[flat|nested] 9+ messages in thread

* Re: [tip:x86/urgent] BUILD SUCCESS WITH WARNING 064855a69003c24bd6b473b367d364e418c57625
  2021-08-19  6:15   ` Chen, Rong A
@ 2021-08-19  9:00     ` Borislav Petkov
  2021-08-19 20:39       ` Reinette Chatre
  0 siblings, 1 reply; 9+ messages in thread
From: Borislav Petkov @ 2021-08-19  9:00 UTC (permalink / raw)
  To: Chen, Rong A, Babu Moger, Reinette Chatre
  Cc: kernel test robot, x86-ml, linux-kernel

On Thu, Aug 19, 2021 at 02:15:16PM +0800, Chen, Rong A wrote:
> 
> 
> On 8/15/2021 4:42 PM, Borislav Petkov wrote:
> > Hi,
> > 
> > On Sun, Aug 15, 2021 at 04:36:40PM +0800, kernel test robot wrote:
> > > tree/branch: https://git.kernel.org/pub/scm/linux/kernel/git/tip/tip.git x86/urgent
> > > branch HEAD: 064855a69003c24bd6b473b367d364e418c57625  x86/resctrl: Fix default monitoring groups reporting
> > > 
> > > possible Warning in current branch:
> > > 
> > > arch/x86/kernel/cpu/resctrl/monitor.c:310 __mon_event_count() error: uninitialized symbol 'm'.
> > > arch/x86/kernel/cpu/resctrl/monitor.c:315 __mon_event_count() error: potentially dereferencing uninitialized 'm'.
> > > 
> > > Warning ids grouped by kconfigs:
> > > 
> > > gcc_recent_errors
> > > `-- i386-randconfig-m021-20210812
> > >      |-- arch-x86-kernel-cpu-resctrl-monitor.c-__mon_event_count()-error:potentially-dereferencing-uninitialized-m-.
> > >      `-- arch-x86-kernel-cpu-resctrl-monitor.c-__mon_event_count()-error:uninitialized-symbol-m-.
> > 
> > AFAIR, I had already asked you guys to make those reports more useful
> > as, for example, adding a link to that randconfig above or even
> > attaching it so that a person - not a machine - reading it, can
> > *actually* act upon it.
> > 
> > But that hasn't happened.
> > 
> > Until it happens, I'm going to ignore all those reports from you.
> > 
> 
> Hi Borislav,
> 
> Sorry about it, the actual link is at https://lists.01.org/hyperkitty/list/kbuild@lists.01.org/thread/PZVMY3VJU4QY4HQXHK3MLPQ2KZ5CNAYH/,
> and it's still an internal report that the robot don't know whether it's a
> false positive or not, we'll update the mail contents to avoid
> misunderstanding.

Aha, ok, smatch thinks that m might not be initialized because

064855a69003 ("x86/resctrl: Fix default monitoring groups reporting")

removed the default case:

-       default:
-               /*
-                * Code would never reach here because
-                * an invalid event id would fail the __rmid_read.
-                */
-               return -EINVAL;

I'm guessing that comment which got removed too, explains why that's ok.

Adding folks to Cc.

Thx.

-- 
Regards/Gruss,
    Boris.

https://people.kernel.org/tglx/notes-about-netiquette

^ permalink raw reply	[flat|nested] 9+ messages in thread

* Re: [tip:x86/urgent] BUILD SUCCESS WITH WARNING 064855a69003c24bd6b473b367d364e418c57625
  2021-08-19  9:00     ` Borislav Petkov
@ 2021-08-19 20:39       ` Reinette Chatre
  2021-08-19 21:05         ` Borislav Petkov
  0 siblings, 1 reply; 9+ messages in thread
From: Reinette Chatre @ 2021-08-19 20:39 UTC (permalink / raw)
  To: Borislav Petkov, Chen, Rong A, Babu Moger
  Cc: kernel test robot, x86-ml, linux-kernel

Hi Borislav and Babu,

On 8/19/2021 2:00 AM, Borislav Petkov wrote:
> On Thu, Aug 19, 2021 at 02:15:16PM +0800, Chen, Rong A wrote:
>>
>>
>> On 8/15/2021 4:42 PM, Borislav Petkov wrote:
>>> Hi,
>>>
>>> On Sun, Aug 15, 2021 at 04:36:40PM +0800, kernel test robot wrote:
>>>> tree/branch: https://git.kernel.org/pub/scm/linux/kernel/git/tip/tip.git x86/urgent
>>>> branch HEAD: 064855a69003c24bd6b473b367d364e418c57625  x86/resctrl: Fix default monitoring groups reporting
>>>>
>>>> possible Warning in current branch:
>>>>
>>>> arch/x86/kernel/cpu/resctrl/monitor.c:310 __mon_event_count() error: uninitialized symbol 'm'.
>>>> arch/x86/kernel/cpu/resctrl/monitor.c:315 __mon_event_count() error: potentially dereferencing uninitialized 'm'.
>>>>
>>>> Warning ids grouped by kconfigs:
>>>>
>>>> gcc_recent_errors
>>>> `-- i386-randconfig-m021-20210812
>>>>       |-- arch-x86-kernel-cpu-resctrl-monitor.c-__mon_event_count()-error:potentially-dereferencing-uninitialized-m-.
>>>>       `-- arch-x86-kernel-cpu-resctrl-monitor.c-__mon_event_count()-error:uninitialized-symbol-m-.
>>>
>>> AFAIR, I had already asked you guys to make those reports more useful
>>> as, for example, adding a link to that randconfig above or even
>>> attaching it so that a person - not a machine - reading it, can
>>> *actually* act upon it.
>>>
>>> But that hasn't happened.
>>>
>>> Until it happens, I'm going to ignore all those reports from you.
>>>
>>
>> Hi Borislav,
>>
>> Sorry about it, the actual link is at https://lists.01.org/hyperkitty/list/kbuild@lists.01.org/thread/PZVMY3VJU4QY4HQXHK3MLPQ2KZ5CNAYH/,
>> and it's still an internal report that the robot don't know whether it's a
>> false positive or not, we'll update the mail contents to avoid
>> misunderstanding.
> 
> Aha, ok, smatch thinks that m might not be initialized because
> 
> 064855a69003 ("x86/resctrl: Fix default monitoring groups reporting")
> 
> removed the default case:
> 
> -       default:
> -               /*
> -                * Code would never reach here because
> -                * an invalid event id would fail the __rmid_read.
> -                */
> -               return -EINVAL;
> 
> I'm guessing that comment which got removed too, explains why that's ok.
> 
> Adding folks to Cc.

I can confirm that the removed comment explains why m would be 
initialized when used in the code that follows.

How would you prefer to address this? We could add just the comment back 
in support of future reports or perhaps by adding the default case back 
with the same error that would be returned earlier when there is an 
invalid EVENT_ID. Something like:

---8<---
diff --git a/arch/x86/kernel/cpu/resctrl/monitor.c 
b/arch/x86/kernel/cpu/resctrl/monitor.c
index 57e4bb695ff9..05b99e4d621c 100644
--- a/arch/x86/kernel/cpu/resctrl/monitor.c
+++ b/arch/x86/kernel/cpu/resctrl/monitor.c
@@ -304,6 +304,12 @@ static u64 __mon_event_count(u32 rmid, struct 
rmid_read *rr)
  	case QOS_L3_MBM_LOCAL_EVENT_ID:
  		m = &rr->d->mbm_local[rmid];
  		break;
+	default:
+		/*
+		 * Code would never reach here because
+		 * an invalid event id would fail the __rmid_read.
+		 */
+		return RMID_VAL_ERROR;
  	}

  	if (rr->first) {




^ permalink raw reply related	[flat|nested] 9+ messages in thread

* Re: [tip:x86/urgent] BUILD SUCCESS WITH WARNING 064855a69003c24bd6b473b367d364e418c57625
  2021-08-19 20:39       ` Reinette Chatre
@ 2021-08-19 21:05         ` Borislav Petkov
  2021-08-20 14:16           ` Babu Moger
  0 siblings, 1 reply; 9+ messages in thread
From: Borislav Petkov @ 2021-08-19 21:05 UTC (permalink / raw)
  To: Reinette Chatre, Babu Moger
  Cc: Chen, Rong A, kernel test robot, x86-ml, linux-kernel

On Thu, Aug 19, 2021 at 01:39:46PM -0700, Reinette Chatre wrote:
> I can confirm that the removed comment explains why m would be initialized
> when used in the code that follows.
> 
> How would you prefer to address this? We could add just the comment back in
> support of future reports or perhaps by adding the default case back with
> the same error that would be returned earlier when there is an invalid
> EVENT_ID. Something like:
> 
> ---8<---
> diff --git a/arch/x86/kernel/cpu/resctrl/monitor.c
> b/arch/x86/kernel/cpu/resctrl/monitor.c
> index 57e4bb695ff9..05b99e4d621c 100644
> --- a/arch/x86/kernel/cpu/resctrl/monitor.c
> +++ b/arch/x86/kernel/cpu/resctrl/monitor.c
> @@ -304,6 +304,12 @@ static u64 __mon_event_count(u32 rmid, struct rmid_read
> *rr)
>  	case QOS_L3_MBM_LOCAL_EVENT_ID:
>  		m = &rr->d->mbm_local[rmid];
>  		break;
> +	default:
> +		/*
> +		 * Code would never reach here because
> +		 * an invalid event id would fail the __rmid_read.
> +		 */
> +		return RMID_VAL_ERROR;
>  	}
> 
>  	if (rr->first) {

Right, I would normally not take a patch just to fix a tool because it
cannot see it correctly.

But Babu has another use case which breaks the build so I guess that's
serious enough to make an exception.

Babu, can you please explain?

Thx.

-- 
Regards/Gruss,
    Boris.

https://people.kernel.org/tglx/notes-about-netiquette

^ permalink raw reply	[flat|nested] 9+ messages in thread

* Re: [tip:x86/urgent] BUILD SUCCESS WITH WARNING 064855a69003c24bd6b473b367d364e418c57625
  2021-08-19 21:05         ` Borislav Petkov
@ 2021-08-20 14:16           ` Babu Moger
  2021-08-20 14:41             ` Reinette Chatre
  0 siblings, 1 reply; 9+ messages in thread
From: Babu Moger @ 2021-08-20 14:16 UTC (permalink / raw)
  To: Borislav Petkov, Reinette Chatre
  Cc: Chen, Rong A, kernel test robot, x86-ml, linux-kernel



On 8/19/21 4:05 PM, Borislav Petkov wrote:
> On Thu, Aug 19, 2021 at 01:39:46PM -0700, Reinette Chatre wrote:
>> I can confirm that the removed comment explains why m would be initialized
>> when used in the code that follows.
>>
>> How would you prefer to address this? We could add just the comment back in
>> support of future reports or perhaps by adding the default case back with
>> the same error that would be returned earlier when there is an invalid
>> EVENT_ID. Something like:
>>
>> ---8<---
>> diff --git a/arch/x86/kernel/cpu/resctrl/monitor.c
>> b/arch/x86/kernel/cpu/resctrl/monitor.c
>> index 57e4bb695ff9..05b99e4d621c 100644
>> --- a/arch/x86/kernel/cpu/resctrl/monitor.c
>> +++ b/arch/x86/kernel/cpu/resctrl/monitor.c
>> @@ -304,6 +304,12 @@ static u64 __mon_event_count(u32 rmid, struct rmid_read
>> *rr)
>>  	case QOS_L3_MBM_LOCAL_EVENT_ID:
>>  		m = &rr->d->mbm_local[rmid];
>>  		break;
>> +	default:
>> +		/*
>> +		 * Code would never reach here because
>> +		 * an invalid event id would fail the __rmid_read.
>> +		 */
>> +		return RMID_VAL_ERROR;
>>  	}
>>
>>  	if (rr->first) {
> 
> Right, I would normally not take a patch just to fix a tool because it
> cannot see it correctly.
> 
> But Babu has another use case which breaks the build so I guess that's
> serious enough to make an exception.
> 
> Babu, can you please explain?

Details:

The patch applies cleanly to RHEL8.5 tree but the build fails with an
uninitialized variable warning treated as an error. The RHEL8.5 Makefile
uses '-Werror=maybe-uninitialized' to force uninitialized variable
warnings to be treated as errors. The build error was found while using
the redhat/configs/kernel-x86_64.config kernel config. BTW, the 5.14-rc6
build passes and it does not build using '-Werror=maybe-uninitialized'.
The error from the build is below:

arch/x86/kernel/cpu/resctrl/monitor.c: In function ‘__mon_event_count’:
arch/x86/kernel/cpu/resctrl/monitor.c:261:12: error: ‘m’ may be used
uninitialized in this function [-Werror=maybe-uninitialized]
  m->chunks += chunks;
            ^~

The following patch fixes the problem.

diff --git a/arch/x86/kernel/cpu/resctrl/monitor.c
b/arch/x86/kernel/cpu/resctrl/monitor.c
index 57e4bb695ff9..553cc6410442 100644
--- a/arch/x86/kernel/cpu/resctrl/monitor.c
+++ b/arch/x86/kernel/cpu/resctrl/monitor.c
@@ -304,6 +304,8 @@ static u64 __mon_event_count(u32 rmid, struct
rmid_read *rr)
        case QOS_L3_MBM_LOCAL_EVENT_ID:
                m = &rr->d->mbm_local[rmid];
                break;
+       default:
+               return RMID_VAL_ERROR;
        }

        if (rr->first) {


Reinette,
Are you going to send the official patch or let me know I will send. You
can add signoff from me after adding above details. We probably need Fixes
and Cc: stable@vger.kernel.org.

thanks
Babu

^ permalink raw reply related	[flat|nested] 9+ messages in thread

* Re: [tip:x86/urgent] BUILD SUCCESS WITH WARNING 064855a69003c24bd6b473b367d364e418c57625
  2021-08-20 14:16           ` Babu Moger
@ 2021-08-20 14:41             ` Reinette Chatre
  0 siblings, 0 replies; 9+ messages in thread
From: Reinette Chatre @ 2021-08-20 14:41 UTC (permalink / raw)
  To: Babu Moger, Borislav Petkov
  Cc: Chen, Rong A, kernel test robot, x86-ml, linux-kernel

Hi Babu,

On 8/20/2021 7:16 AM, Babu Moger wrote:
> 
> 
> On 8/19/21 4:05 PM, Borislav Petkov wrote:
>> On Thu, Aug 19, 2021 at 01:39:46PM -0700, Reinette Chatre wrote:
>>> I can confirm that the removed comment explains why m would be initialized
>>> when used in the code that follows.
>>>
>>> How would you prefer to address this? We could add just the comment back in
>>> support of future reports or perhaps by adding the default case back with
>>> the same error that would be returned earlier when there is an invalid
>>> EVENT_ID. Something like:
>>>
>>> ---8<---
>>> diff --git a/arch/x86/kernel/cpu/resctrl/monitor.c
>>> b/arch/x86/kernel/cpu/resctrl/monitor.c
>>> index 57e4bb695ff9..05b99e4d621c 100644
>>> --- a/arch/x86/kernel/cpu/resctrl/monitor.c
>>> +++ b/arch/x86/kernel/cpu/resctrl/monitor.c
>>> @@ -304,6 +304,12 @@ static u64 __mon_event_count(u32 rmid, struct rmid_read
>>> *rr)
>>>   	case QOS_L3_MBM_LOCAL_EVENT_ID:
>>>   		m = &rr->d->mbm_local[rmid];
>>>   		break;
>>> +	default:
>>> +		/*
>>> +		 * Code would never reach here because
>>> +		 * an invalid event id would fail the __rmid_read.
>>> +		 */
>>> +		return RMID_VAL_ERROR;
>>>   	}
>>>
>>>   	if (rr->first) {
>>
>> Right, I would normally not take a patch just to fix a tool because it
>> cannot see it correctly.
>>
>> But Babu has another use case which breaks the build so I guess that's
>> serious enough to make an exception.
>>
>> Babu, can you please explain?
> 
> Details:
> 
> The patch applies cleanly to RHEL8.5 tree but the build fails with an
> uninitialized variable warning treated as an error. The RHEL8.5 Makefile
> uses '-Werror=maybe-uninitialized' to force uninitialized variable
> warnings to be treated as errors. The build error was found while using
> the redhat/configs/kernel-x86_64.config kernel config. BTW, the 5.14-rc6
> build passes and it does not build using '-Werror=maybe-uninitialized'.
> The error from the build is below:
> 
> arch/x86/kernel/cpu/resctrl/monitor.c: In function ‘__mon_event_count’:
> arch/x86/kernel/cpu/resctrl/monitor.c:261:12: error: ‘m’ may be used
> uninitialized in this function [-Werror=maybe-uninitialized]
>    m->chunks += chunks;
>              ^~
> 
> The following patch fixes the problem.
> 
> diff --git a/arch/x86/kernel/cpu/resctrl/monitor.c
> b/arch/x86/kernel/cpu/resctrl/monitor.c
> index 57e4bb695ff9..553cc6410442 100644
> --- a/arch/x86/kernel/cpu/resctrl/monitor.c
> +++ b/arch/x86/kernel/cpu/resctrl/monitor.c
> @@ -304,6 +304,8 @@ static u64 __mon_event_count(u32 rmid, struct
> rmid_read *rr)
>          case QOS_L3_MBM_LOCAL_EVENT_ID:
>                  m = &rr->d->mbm_local[rmid];
>                  break;
> +       default:
> +               return RMID_VAL_ERROR;
>          }
> 
>          if (rr->first) {
> 
> 
> Reinette,
> Are you going to send the official patch or let me know I will send. You
> can add signoff from me after adding above details. We probably need Fixes
> and Cc: stable@vger.kernel.org.
> 

Could you please go ahead and send a patch with these details you 
collected?

Thank you very much

Reinette

^ permalink raw reply	[flat|nested] 9+ messages in thread

end of thread, other threads:[~2021-08-20 14:42 UTC | newest]

Thread overview: 9+ messages (download: mbox.gz / follow: Atom feed)
-- links below jump to the message on this page --
2021-08-15  8:36 [tip:x86/urgent] BUILD SUCCESS WITH WARNING 064855a69003c24bd6b473b367d364e418c57625 kernel test robot
2021-08-15  8:42 ` Borislav Petkov
2021-08-15 10:22   ` Philip Li
2021-08-19  6:15   ` Chen, Rong A
2021-08-19  9:00     ` Borislav Petkov
2021-08-19 20:39       ` Reinette Chatre
2021-08-19 21:05         ` Borislav Petkov
2021-08-20 14:16           ` Babu Moger
2021-08-20 14:41             ` Reinette Chatre

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