From: Arvind Sankar <nivedita@alum.mit.edu>
To: Ard Biesheuvel <ardb@kernel.org>
Cc: linux-kernel@vger.kernel.org, linux-efi@vger.kernel.org,
Hans de Goede <hdegoede@redhat.com>,
Matthew Garrett <matthewgarrett@google.com>,
Ingo Molnar <mingo@kernel.org>, Andy Lutomirski <luto@kernel.org>,
Thomas Gleixner <tglx@linutronix.de>,
Arvind Sankar <nivedita@alum.mit.edu>
Subject: Re: [PATCH 05/10] efi/libstub: distinguish between native/mixed not 32/64 bit
Date: Sat, 14 Dec 2019 14:46:27 -0500 [thread overview]
Message-ID: <20191214194626.GA140998@rani.riverdale.lan> (raw)
In-Reply-To: <20191214175735.22518-6-ardb@kernel.org>
On Sat, Dec 14, 2019 at 06:57:30PM +0100, Ard Biesheuvel wrote:
> +
> +#define efi_table_attr(table, attr, instance) ({ \
> + __typeof__(((table##_t *)0)->attr) __ret; \
> + if (efi_is_native()) { \
> + __ret = ((table##_t *)instance)->attr; \
> + } else { \
> + __typeof__(((table##_32_t *)0)->attr) at; \
> + at = (((table##_32_t *)(unsigned long)instance)->attr); \
> + __ret = (__typeof__(__ret))(unsigned long)at; \
> + } \
> + __ret; \
> +})
The casting of `at' is appropriate if the attr is a pointer type which
needs to be zero-extended to 64-bit, but for other fields it is
unnecessary at best and possibly dangerous. There are probably no
instances currently where it is called for a non-pointer field, but is
it possible to detect if the type is pointer and avoid the cast if not?
next prev parent reply other threads:[~2019-12-14 19:46 UTC|newest]
Thread overview: 29+ messages / expand[flat|nested] mbox.gz Atom feed top
2019-12-14 17:57 [PATCH 00/10] efi/x86: confine type unsafe casting to mixed mode Ard Biesheuvel
2019-12-14 17:57 ` [PATCH 01/10] efi/libstub: remove unused __efi_call_early() macro Ard Biesheuvel
2019-12-14 17:57 ` [PATCH 02/10] efi/x86: rename efi_is_native() to efi_is_mixed() Ard Biesheuvel
2019-12-14 17:57 ` [PATCH 03/10] efi/libstub: use a helper to iterate over a EFI handle array Ard Biesheuvel
2019-12-14 20:32 ` Arvind Sankar
2019-12-14 20:40 ` Ard Biesheuvel
2019-12-14 21:04 ` Ard Biesheuvel
2019-12-14 21:11 ` Arvind Sankar
2019-12-14 21:07 ` Arvind Sankar
2019-12-14 17:57 ` [PATCH 04/10] efi/libstub: add missing apple_properties_protocol_t definition Ard Biesheuvel
2019-12-14 17:57 ` [PATCH 05/10] efi/libstub: distinguish between native/mixed not 32/64 bit Ard Biesheuvel
2019-12-14 19:46 ` Arvind Sankar [this message]
2019-12-14 19:49 ` Arvind Sankar
2019-12-14 19:54 ` Ard Biesheuvel
2019-12-14 20:13 ` Arvind Sankar
2019-12-14 20:27 ` Ard Biesheuvel
2019-12-14 21:17 ` Arvind Sankar
2019-12-14 21:30 ` Ard Biesheuvel
2019-12-14 22:14 ` Arvind Sankar
2019-12-14 22:14 ` Ard Biesheuvel
2019-12-14 23:02 ` Arvind Sankar
2019-12-14 17:57 ` [PATCH 06/10] efi/libstub/x86: use mixed mode helpers to populate efi_config Ard Biesheuvel
2019-12-14 17:57 ` [PATCH 07/10] efi/libstub: drop explicit 64-bit protocol definitions Ard Biesheuvel
2019-12-14 17:57 ` [PATCH 08/10] efi/libstub: use stricter typing for firmware function pointers Ard Biesheuvel
2019-12-14 17:57 ` [PATCH 09/10] efi/libstub: annotate firmware routines as __efiapi Ard Biesheuvel
2019-12-17 15:01 ` Brian Gerst
2019-12-14 17:57 ` [PATCH 10/10] efi/libstub/x86: avoid thunking for native firmware calls Ard Biesheuvel
2019-12-15 19:30 ` Arvind Sankar
2019-12-17 8:32 ` Ard Biesheuvel
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=20191214194626.GA140998@rani.riverdale.lan \
--to=nivedita@alum.mit.edu \
--cc=ardb@kernel.org \
--cc=hdegoede@redhat.com \
--cc=linux-efi@vger.kernel.org \
--cc=linux-kernel@vger.kernel.org \
--cc=luto@kernel.org \
--cc=matthewgarrett@google.com \
--cc=mingo@kernel.org \
--cc=tglx@linutronix.de \
/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
all inboxes | Powered by JetHome®