From: "Rafael J. Wysocki" <rafael@kernel.org>
To: Arnd Bergmann <arnd@kernel.org>
Cc: Len Brown <lenb@kernel.org>,
Robert Moore <robert.moore@intel.com>,
Arnd Bergmann <arnd@arndb.de>,
"Rafael J. Wysocki" <rafael.j.wysocki@intel.com>,
Nathan Chancellor <nathan@kernel.org>,
Nick Desaulniers <ndesaulniers@google.com>,
Erik Kaneda <erik.kaneda@intel.com>,
ACPI Devel Maling List <linux-acpi@vger.kernel.org>,
"open list:ACPI COMPONENT ARCHITECTURE (ACPICA)"
<devel@acpica.org>,
Linux Kernel Mailing List <linux-kernel@vger.kernel.org>,
llvm@lists.linux.dev
Subject: Re: [PATCH] ACPI: avoid NULL pointer arithmetic
Date: Thu, 30 Sep 2021 20:52:59 +0200 [thread overview]
Message-ID: <CAJZ5v0jDKK6ecsubVDv_=EUF3goiiDW28tvbKF9cesMphgKaug@mail.gmail.com> (raw)
In-Reply-To: <CAJZ5v0jJRYQPSfVV_hCD6uxch+vU6kvWV9-KAfqHckHgkFOeaA@mail.gmail.com>
On Wed, Sep 29, 2021 at 8:47 PM Rafael J. Wysocki <rafael@kernel.org> wrote:
>
> On Mon, Sep 27, 2021 at 2:13 PM Arnd Bergmann <arnd@kernel.org> wrote:
> >
> > From: Arnd Bergmann <arnd@arndb.de>
> >
> > There are some very old macros for doing an open-coded offsetof() and
> > cast between pointer and integer in ACPI headers. clang-14 now complains
> > about these:
> >
> > drivers/acpi/acpica/tbfadt.c:86:3: error: performing pointer subtraction with a null pointer has undefined behavior [-Werror,-Wnull-pointer-subtraction]
> > ACPI_FADT_OFFSET(pm_timer_block),
> > ^~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
> > include/acpi/actbl.h:376:47: note: expanded from macro 'ACPI_FADT_OFFSET'
> > #define ACPI_FADT_OFFSET(f) (u16) ACPI_OFFSET (struct acpi_table_fadt, f)
> > ^~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
> > include/acpi/actypes.h:511:41: note: expanded from macro 'ACPI_OFFSET'
> > #define ACPI_OFFSET(d, f) ACPI_PTR_DIFF (&(((d *) 0)->f), (void *) 0)
> > ^~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
> > include/acpi/actypes.h:505:79: note: expanded from macro 'ACPI_PTR_DIFF'
> > #define ACPI_PTR_DIFF(a, b) ((acpi_size) (ACPI_CAST_PTR (u8, (a)) - ACPI_CAST_PTR (u8, (b))))
> > ^ ~~~~~~~~~~~~~~~~~~~~~~~
> > Convert them to the modern equivalents.
> >
> > Signed-off-by: Arnd Bergmann <arnd@arndb.de>
> > ---
> > include/acpi/actypes.h | 4 ++--
> > 1 file changed, 2 insertions(+), 2 deletions(-)
> >
> > diff --git a/include/acpi/actypes.h b/include/acpi/actypes.h
> > index 92c71dfce0d5..285bc7b73de3 100644
> > --- a/include/acpi/actypes.h
> > +++ b/include/acpi/actypes.h
> > @@ -507,8 +507,8 @@ typedef u64 acpi_integer;
> > /* Pointer/Integer type conversions */
> >
> > #define ACPI_TO_POINTER(i) ACPI_CAST_PTR (void, (acpi_size) (i))
> > -#define ACPI_TO_INTEGER(p) ACPI_PTR_DIFF (p, (void *) 0)
> > -#define ACPI_OFFSET(d, f) ACPI_PTR_DIFF (&(((d *) 0)->f), (void *) 0)
> > +#define ACPI_TO_INTEGER(p) ((uintptr_t)(p))
> > +#define ACPI_OFFSET(d, f) offsetof(d, f)
> > #define ACPI_PHYSADDR_TO_PTR(i) ACPI_TO_POINTER(i)
> > #define ACPI_PTR_TO_PHYSADDR(i) ACPI_TO_INTEGER(i)
> >
> > --
>
> Queued up as 5.16 material, converted into an upstream ACPICA pull
> request and submitted, thanks!
And reverted from there, because it introduced build issues.
Can we use alternative definitions that don't depend on uintptr_t and
offsetof()?
next prev parent reply other threads:[~2021-09-30 18:53 UTC|newest]
Thread overview: 7+ messages / expand[flat|nested] mbox.gz Atom feed top
2021-09-27 12:13 [PATCH] ACPI: avoid NULL pointer arithmetic Arnd Bergmann
2021-09-28 17:43 ` Rafael J. Wysocki
2021-09-28 20:39 ` Moore, Robert
2021-09-29 12:01 ` Rafael J. Wysocki
2021-09-29 18:47 ` Rafael J. Wysocki
2021-09-30 18:52 ` Rafael J. Wysocki [this message]
2021-09-30 20:36 ` Arnd Bergmann
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='CAJZ5v0jDKK6ecsubVDv_=EUF3goiiDW28tvbKF9cesMphgKaug@mail.gmail.com' \
--to=rafael@kernel.org \
--cc=arnd@arndb.de \
--cc=arnd@kernel.org \
--cc=devel@acpica.org \
--cc=erik.kaneda@intel.com \
--cc=lenb@kernel.org \
--cc=linux-acpi@vger.kernel.org \
--cc=linux-kernel@vger.kernel.org \
--cc=llvm@lists.linux.dev \
--cc=nathan@kernel.org \
--cc=ndesaulniers@google.com \
--cc=rafael.j.wysocki@intel.com \
--cc=robert.moore@intel.com \
/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).