From: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
To: Andy Shevchenko <andriy.shevchenko@linux.intel.com>
Cc: Alexander Shishkin <alexander.shishkin@linux.intel.com>,
linux-kernel@vger.kernel.org
Subject: Re: [PATCH 2/7] stm class: Replace uuid_t with plain u8 uuid[16]
Date: Wed, 14 Apr 2021 20:56:50 +0200 [thread overview]
Message-ID: <YHc68v7keeITnA3K@kroah.com> (raw)
In-Reply-To: <YHcqxMLR44laX2PZ@smile.fi.intel.com>
On Wed, Apr 14, 2021 at 08:47:48PM +0300, Andy Shevchenko wrote:
> On Wed, Apr 14, 2021 at 07:33:38PM +0200, Greg Kroah-Hartman wrote:
> > On Wed, Apr 14, 2021 at 08:12:46PM +0300, Alexander Shishkin wrote:
> > > From: Andy Shevchenko <andriy.shevchenko@linux.intel.com>
> > >
> > > It appears that uuid_t use in STM code abuses UUID API.
> >
> > How is it being abused?
>
> We are using it against the buffer that is u8, and neither uuid_t nor guid_t.
And how should it be used?
> > Moreover,
> > > this type is only useful when we parse user input. Due to above
> > > replace uuid_t with u8 uuid[16] and use uuid_t only when parse
> > > user input.
> > >
> > > Signed-off-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com>
> > > Signed-off-by: Alexander Shishkin <alexander.shishkin@linux.intel.com>
> > > ---
> > > drivers/hwtracing/stm/p_sys-t.c | 16 ++++++++++------
> > > 1 file changed, 10 insertions(+), 6 deletions(-)
> > >
> > > diff --git a/drivers/hwtracing/stm/p_sys-t.c b/drivers/hwtracing/stm/p_sys-t.c
> > > index 360b5c03df95..04d13b3785d3 100644
> > > --- a/drivers/hwtracing/stm/p_sys-t.c
> > > +++ b/drivers/hwtracing/stm/p_sys-t.c
> > > @@ -76,7 +76,7 @@ enum sys_t_message_string_subtype {
> > > MIPI_SYST_SEVERITY(MAX))
> > >
> > > struct sys_t_policy_node {
> > > - uuid_t uuid;
> > > + u8 uuid[UUID_SIZE];
> >
> > This feels wrong, what is wrong with the uuid_t type usage here?
>
> Nothing, just will require additional export_uuid() / import_uuid() call.
Isn't that the "correct way" here?
> > > bool do_len;
> > > unsigned long ts_interval;
> > > unsigned long clocksync_interval;
> > > @@ -92,7 +92,7 @@ static void sys_t_policy_node_init(void *priv)
> > > {
> > > struct sys_t_policy_node *pn = priv;
> > >
> > > - generate_random_uuid(pn->uuid.b);
> >
> > Ok, that's not good, but that looks to be a flaw in the
> > generate_random_uuid() api, not this driver implementation.
> >
> > I don't understand why this change is needed?
>
> Using raw buffer APIs against uuid_t / guid_t.
So you want to do that, or you do not want to do that? Totally
confused,
greg k-h
next prev parent reply other threads:[~2021-04-14 18:57 UTC|newest]
Thread overview: 18+ messages / expand[flat|nested] mbox.gz Atom feed top
2021-04-14 17:12 [PATCH 0/7] stm class/intel_th: Updates for v5.13 Alexander Shishkin
2021-04-14 17:12 ` [PATCH 1/7] stm class: Remove an unused function Alexander Shishkin
2021-04-14 17:12 ` [PATCH 2/7] stm class: Replace uuid_t with plain u8 uuid[16] Alexander Shishkin
2021-04-14 17:33 ` Greg Kroah-Hartman
2021-04-14 17:47 ` Andy Shevchenko
2021-04-14 18:56 ` Greg Kroah-Hartman [this message]
2021-04-14 19:12 ` Andy Shevchenko
2021-04-14 19:14 ` Alexander Shishkin
2021-04-14 19:16 ` Andy Shevchenko
2021-04-15 8:34 ` Greg Kroah-Hartman
2021-04-15 8:48 ` Andy Shevchenko
2021-04-15 9:08 ` Greg Kroah-Hartman
2021-04-15 9:20 ` Alexander Shishkin
2021-04-14 17:12 ` [PATCH 3/7] intel_th: Constify all drvdata references Alexander Shishkin
2021-04-14 17:12 ` [PATCH 4/7] intel_th: Constify attribute_group structs Alexander Shishkin
2021-04-14 17:12 ` [PATCH 5/7] intel_th: Consistency and off-by-one fix Alexander Shishkin
2021-04-14 17:12 ` [PATCH 6/7] intel_th: pci: Add Rocket Lake CPU support Alexander Shishkin
2021-04-14 17:12 ` [PATCH 7/7] intel_th: pci: Add Alder Lake-M support Alexander Shishkin
Reply instructions:
You may reply publicly to this message via plain-text email
using any one of the following methods:
* Save the following mbox file, import it into your mail client,
and reply-to-all from there: mbox
Avoid top-posting and favor interleaved quoting:
https://en.wikipedia.org/wiki/Posting_style#Interleaved_style
* Reply using the --to, --cc, and --in-reply-to
switches of git-send-email(1):
git send-email \
--in-reply-to=YHc68v7keeITnA3K@kroah.com \
--to=gregkh@linuxfoundation.org \
--cc=alexander.shishkin@linux.intel.com \
--cc=andriy.shevchenko@linux.intel.com \
--cc=linux-kernel@vger.kernel.org \
/path/to/YOUR_REPLY
https://kernel.org/pub/software/scm/git/docs/git-send-email.html
* If your mail client supports setting the In-Reply-To header
via mailto: links, try the mailto: link
Be sure your reply has a Subject: header at the top and a blank line
before the message body.
This is a public inbox, see mirroring instructions
for how to clone and mirror all data and code used for this inbox;
as well as URLs for NNTP newsgroup(s).