| Message ID | 20180110163633.GA24230@bogon.didichuxing.com (mailing list archive) |
|---|---|
| State | New, archived |
| Headers | show |
2018-01-11 0:36 GMT+08:00 weiping zhang <zhangweiping@didichuxing.com>: > bdi debugfs dir/file may create fail, add error log here. > > Signed-off-by: weiping zhang <zhangweiping@didichuxing.com> > --- > V1->V2: > fix indentation and make log message more clear > > mm/backing-dev.c | 4 +++- > 1 file changed, 3 insertions(+), 1 deletion(-) > > diff --git a/mm/backing-dev.c b/mm/backing-dev.c > index b5f940c..0a49665 100644 > --- a/mm/backing-dev.c > +++ b/mm/backing-dev.c > @@ -885,7 +885,9 @@ int bdi_register_va(struct backing_dev_info *bdi, const char *fmt, va_list args) > cgwb_bdi_register(bdi); > bdi->dev = dev; > > - bdi_debug_register(bdi, dev_name(dev)); > + if (bdi_debug_register(bdi, dev_name(dev))) > + pr_warn("blkdev %s: creation of bdi debugfs entries failed.\n", > + dev_name(dev)); > set_bit(WB_registered, &bdi->wb.state); > > spin_lock_bh(&bdi_lock); > -- Hi Jens, madam has no permission to create debuts entry if SELINUX is enable at Fedora and Centos, and we have revert 6d0e4827b72 Revert "bdi: add error handle for bdi_debug_register", that is to say bdi debugfs is not the key component of block device, this patch just add warning log. Thanks
On 1/19/18 10:36 AM, weiping zhang wrote: > 2018-01-11 0:36 GMT+08:00 weiping zhang <zhangweiping@didichuxing.com>: >> bdi debugfs dir/file may create fail, add error log here. >> >> Signed-off-by: weiping zhang <zhangweiping@didichuxing.com> >> --- >> V1->V2: >> fix indentation and make log message more clear >> >> mm/backing-dev.c | 4 +++- >> 1 file changed, 3 insertions(+), 1 deletion(-) >> >> diff --git a/mm/backing-dev.c b/mm/backing-dev.c >> index b5f940c..0a49665 100644 >> --- a/mm/backing-dev.c >> +++ b/mm/backing-dev.c >> @@ -885,7 +885,9 @@ int bdi_register_va(struct backing_dev_info *bdi, const char *fmt, va_list args) >> cgwb_bdi_register(bdi); >> bdi->dev = dev; >> >> - bdi_debug_register(bdi, dev_name(dev)); >> + if (bdi_debug_register(bdi, dev_name(dev))) >> + pr_warn("blkdev %s: creation of bdi debugfs entries failed.\n", >> + dev_name(dev)); >> set_bit(WB_registered, &bdi->wb.state); >> >> spin_lock_bh(&bdi_lock); >> -- > > Hi Jens, > > madam has no permission to create debuts entry if SELINUX is enable at > Fedora and Centos, > and we have revert 6d0e4827b72 Revert "bdi: add error handle for > bdi_debug_register", that is to say > bdi debugfs is not the key component of block device, this patch just > add warning log. Have we fixed the case where we know it will trigger?
2018-01-20 3:54 GMT+08:00 Jens Axboe <axboe@kernel.dk>: > On 1/19/18 10:36 AM, weiping zhang wrote: >> 2018-01-11 0:36 GMT+08:00 weiping zhang <zhangweiping@didichuxing.com>: >>> bdi debugfs dir/file may create fail, add error log here. >>> >>> Signed-off-by: weiping zhang <zhangweiping@didichuxing.com> >>> --- >>> V1->V2: >>> fix indentation and make log message more clear >>> >>> mm/backing-dev.c | 4 +++- >>> 1 file changed, 3 insertions(+), 1 deletion(-) >>> >>> diff --git a/mm/backing-dev.c b/mm/backing-dev.c >>> index b5f940c..0a49665 100644 >>> --- a/mm/backing-dev.c >>> +++ b/mm/backing-dev.c >>> @@ -885,7 +885,9 @@ int bdi_register_va(struct backing_dev_info *bdi, const char *fmt, va_list args) >>> cgwb_bdi_register(bdi); >>> bdi->dev = dev; >>> >>> - bdi_debug_register(bdi, dev_name(dev)); >>> + if (bdi_debug_register(bdi, dev_name(dev))) >>> + pr_warn("blkdev %s: creation of bdi debugfs entries failed.\n", >>> + dev_name(dev)); >>> set_bit(WB_registered, &bdi->wb.state); >>> >>> spin_lock_bh(&bdi_lock); >>> -- >> >> Hi Jens, >> >> madam has no permission to create debuts entry if SELINUX is enable at >> Fedora and Centos, >> and we have revert 6d0e4827b72 Revert "bdi: add error handle for >> bdi_debug_register", that is to say >> bdi debugfs is not the key component of block device, this patch just >> add warning log. > > Have we fixed the case where we know it will trigger? The reason is that mdadm has no permission to create dir/file under /sys/kernel/debug/ , I think we can solve it in two possible ways. 1.Add proper SELINUX policy to allow mdadm create /sys/kernel/debug/bdi/xxx, but not every user add this allowance, so kernel show a warning for this case. 2.Split mdadm into 2 part, Firstly, user proccess mdadm trigger a kwork and wait a event done, secondly kwork will create gendisk)and then wake up event. But it is more likely a hack, and it may break SELINUX mechanism, so I give up this way. https://marc.info/?l=linux-mm&m=151456540928231&w=2 > -- > Jens Axboe >
diff --git a/mm/backing-dev.c b/mm/backing-dev.c index b5f940c..0a49665 100644 --- a/mm/backing-dev.c +++ b/mm/backing-dev.c @@ -885,7 +885,9 @@ int bdi_register_va(struct backing_dev_info *bdi, const char *fmt, va_list args) cgwb_bdi_register(bdi); bdi->dev = dev; - bdi_debug_register(bdi, dev_name(dev)); + if (bdi_debug_register(bdi, dev_name(dev))) + pr_warn("blkdev %s: creation of bdi debugfs entries failed.\n", + dev_name(dev)); set_bit(WB_registered, &bdi->wb.state); spin_lock_bh(&bdi_lock);
bdi debugfs dir/file may create fail, add error log here. Signed-off-by: weiping zhang <zhangweiping@didichuxing.com> --- V1->V2: fix indentation and make log message more clear mm/backing-dev.c | 4 +++- 1 file changed, 3 insertions(+), 1 deletion(-)