linux-api.vger.kernel.org archive mirror
 help / color / mirror / Atom feed
From: Michael Ellerman <mpe@ellerman.id.au>
To: Sohil Mehta <sohil.mehta@intel.com>,
	linux-api@vger.kernel.org, linux-arch@vger.kernel.org
Cc: Sohil Mehta <sohil.mehta@intel.com>,
	Richard Henderson <richard.henderson@linaro.org>,
	Ivan Kokshaysky <ink@jurassic.park.msu.ru>,
	Matt Turner <mattst88@gmail.com>,
	Russell King <linux@armlinux.org.uk>,
	Catalin Marinas <catalin.marinas@arm.com>,
	Will Deacon <will@kernel.org>,
	Geert Uytterhoeven <geert@linux-m68k.org>,
	Michal Simek <monstr@monstr.eu>,
	Thomas Bogendoerfer <tsbogend@alpha.franken.de>,
	"James E . J . Bottomley" <James.Bottomley@HansenPartnership.com>,
	Helge Deller <deller@gmx.de>, Nicholas Piggin <npiggin@gmail.com>,
	Christophe Leroy <christophe.leroy@csgroup.eu>,
	Heiko Carstens <hca@linux.ibm.com>,
	Vasily Gorbik <gor@linux.ibm.com>,
	Alexander Gordeev <agordeev@linux.ibm.com>,
	Christian Borntraeger <borntraeger@linux.ibm.com>,
	Sven Schnelle <svens@linux.ibm.com>,
	Yoshinori Sato <ysato@users.sourceforge.jp>,
	Rich Felker <dalias@libc.org>,
	John Paul Adrian Glaubitz <glaubitz@physik.fu-berlin.de>,
	"David S . Miller" <davem@davemloft.net>,
	Andy Lutomirski <luto@kernel.org>,
	Thomas Gleixner <tglx@linutronix.de>,
	Ingo Molnar <mingo@redhat.com>, Borislav Petkov <bp@alien8.de>,
	Dave Hansen <dave.hansen@linux.intel.com>,
	x86@kernel.org, "H . Peter Anvin" <hpa@zytor.com>,
	Chris Zankel <chris@zankel.net>,
	Max Filippov <jcmvbkbc@gmail.com>, Arnd Bergmann <arnd@arndb.de>,
	Peter Zijlstra <peterz@infradead.org>,
	Arnaldo Carvalho de Melo <acme@kernel.org>,
	Mark Rutland <mark.rutland@arm.com>,
	Alexander Shishkin <alexander.shishkin@linux.intel.com>,
	Jiri Olsa <jolsa@kernel.org>, Namhyung Kim <namhyung@kernel.org>,
	Ian Rogers <irogers@google.com>,
	Adrian Hunter <adrian.hunter@intel.com>,
	Lukas Bulwahn <lukas.bulwahn@gmail.com>,
	Sergei Trofimovich <slyich@gmail.com>,
	Andrew Morton <akpm@linux-foundation.org>,
	Rohan McLure <rmclure@linux.ibm.com>,
	Andreas Schwab <schwab@linux-m68k.org>,
	"Eric W . Biederman" <ebiederm@xmission.com>,
	Brian Gerst <brgerst@gmail.com>,
	Randy Dunlap <rdunlap@infradead.org>,
	Rick Edgecombe <rick.p.edgecombe@intel.com>,
	Mark Brown <broonie@kernel.org>,
	Deepak Gupta <debug@rivosinc.com>,
	linux-alpha@vger.kernel.org, linux-kernel@vger.kernel.org,
	linux-arm-kernel@lists.infradead.org, linux-ia64@vger.kernel.org,
	linux-m68k@lists.linux-m68k.org, linux-mips@vger.kernel.org,
	linux-parisc@vger.kernel.org, linuxppc-dev@lists.ozlabs.org,
	linux-s390@vger.kernel.org, linux-sh@vger.kernel.org,
	sparclinux@vger.kernel.org, linux-perf-users@vger.kernel.org
Subject: Re: [PATCH v2] arch: Reserve map_shadow_stack() syscall number for all architectures
Date: Fri, 15 Sep 2023 13:23:43 +1000	[thread overview]
Message-ID: <878r986rwg.fsf@mail.lhotse> (raw)
In-Reply-To: <20230914185804.2000497-1-sohil.mehta@intel.com>

Sohil Mehta <sohil.mehta@intel.com> writes:
> commit c35559f94ebc ("x86/shstk: Introduce map_shadow_stack syscall")
> recently added support for map_shadow_stack() but it is limited to x86
> only for now. There is a possibility that other architectures (namely,
> arm64 and RISC-V), that are implementing equivalent support for shadow
> stacks, might need to add support for it.
>
> Independent of that, reserving arch-specific syscall numbers in the
> syscall tables of all architectures is good practice and would help
> avoid future conflicts. map_shadow_stack() is marked as a conditional
> syscall in sys_ni.c. Adding it to the syscall tables of other
> architectures is harmless and would return ENOSYS when exercised.
>
> Note, map_shadow_stack() was assigned #453 during the merge process
> since #452 was taken by fchmodat2().
>
> For Powerpc, map it to sys_ni_syscall() as is the norm for Powerpc
> syscall tables.

Mapping it to sys_map_shadow_stack() would work fine, but I'm happy with
sys_ni_syscall as I don't see powerpc implementing map_shadow_stack()
any time soon.

Acked-by: Michael Ellerman <mpe@ellerman.id.au> (powerpc)

cheers

  parent reply	other threads:[~2023-09-15  3:24 UTC|newest]

Thread overview: 11+ messages / expand[flat|nested]  mbox.gz  Atom feed  top
2023-09-14 18:58 [PATCH v2] arch: Reserve map_shadow_stack() syscall number for all architectures Sohil Mehta
2023-09-14 22:08 ` Edgecombe, Rick P
2023-09-15  3:23 ` Michael Ellerman [this message]
2023-10-03 16:35 ` Sohil Mehta
2023-10-03 16:54   ` Arnd Bergmann
2023-10-03 17:18     ` Sohil Mehta
2023-10-06 20:01       ` Edgecombe, Rick P
2023-10-06 20:29         ` Arnd Bergmann
2023-10-06 20:36           ` Sohil Mehta
2023-10-03 17:19 ` Geert Uytterhoeven
2023-10-04  7:22 ` Catalin Marinas

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=878r986rwg.fsf@mail.lhotse \
    --to=mpe@ellerman.id.au \
    --cc=James.Bottomley@HansenPartnership.com \
    --cc=acme@kernel.org \
    --cc=adrian.hunter@intel.com \
    --cc=agordeev@linux.ibm.com \
    --cc=akpm@linux-foundation.org \
    --cc=alexander.shishkin@linux.intel.com \
    --cc=arnd@arndb.de \
    --cc=borntraeger@linux.ibm.com \
    --cc=bp@alien8.de \
    --cc=brgerst@gmail.com \
    --cc=broonie@kernel.org \
    --cc=catalin.marinas@arm.com \
    --cc=chris@zankel.net \
    --cc=christophe.leroy@csgroup.eu \
    --cc=dalias@libc.org \
    --cc=dave.hansen@linux.intel.com \
    --cc=davem@davemloft.net \
    --cc=debug@rivosinc.com \
    --cc=deller@gmx.de \
    --cc=ebiederm@xmission.com \
    --cc=geert@linux-m68k.org \
    --cc=glaubitz@physik.fu-berlin.de \
    --cc=gor@linux.ibm.com \
    --cc=hca@linux.ibm.com \
    --cc=hpa@zytor.com \
    --cc=ink@jurassic.park.msu.ru \
    --cc=irogers@google.com \
    --cc=jcmvbkbc@gmail.com \
    --cc=jolsa@kernel.org \
    --cc=linux-alpha@vger.kernel.org \
    --cc=linux-api@vger.kernel.org \
    --cc=linux-arch@vger.kernel.org \
    --cc=linux-arm-kernel@lists.infradead.org \
    --cc=linux-ia64@vger.kernel.org \
    --cc=linux-kernel@vger.kernel.org \
    --cc=linux-m68k@lists.linux-m68k.org \
    --cc=linux-mips@vger.kernel.org \
    --cc=linux-parisc@vger.kernel.org \
    --cc=linux-perf-users@vger.kernel.org \
    --cc=linux-s390@vger.kernel.org \
    --cc=linux-sh@vger.kernel.org \
    --cc=linux@armlinux.org.uk \
    --cc=linuxppc-dev@lists.ozlabs.org \
    --cc=lukas.bulwahn@gmail.com \
    --cc=luto@kernel.org \
    --cc=mark.rutland@arm.com \
    --cc=mattst88@gmail.com \
    --cc=mingo@redhat.com \
    --cc=monstr@monstr.eu \
    --cc=namhyung@kernel.org \
    --cc=npiggin@gmail.com \
    --cc=peterz@infradead.org \
    --cc=rdunlap@infradead.org \
    --cc=richard.henderson@linaro.org \
    --cc=rick.p.edgecombe@intel.com \
    --cc=rmclure@linux.ibm.com \
    --cc=schwab@linux-m68k.org \
    --cc=slyich@gmail.com \
    --cc=sohil.mehta@intel.com \
    --cc=sparclinux@vger.kernel.org \
    --cc=svens@linux.ibm.com \
    --cc=tglx@linutronix.de \
    --cc=tsbogend@alpha.franken.de \
    --cc=will@kernel.org \
    --cc=x86@kernel.org \
    --cc=ysato@users.sourceforge.jp \
    /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).