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Date:   Tue, 3 Oct 2023 10:47:06 -0700
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Subject: Re: [PATCH v2] syscalls: Cleanup references to sys_lookup_dcookie()
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From:   Sohil Mehta <sohil.mehta@intel.com>
To:     Arnd Bergmann <arnd@arndb.de>, <linux-api@vger.kernel.org>,
        <linux-arch@vger.kernel.org>
CC:     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>,
        Michael Ellerman <mpe@ellerman.id.au>,
        "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>,
        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>,
        <linux-alpha@vger.kernel.org>, <linux-kernel@vger.kernel.org>,
        <linux-arm-kernel@lists.infradead.org>,
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References: <20230628230935.1196180-1-sohil.mehta@intel.com>
 <20230710185124.3848462-1-sohil.mehta@intel.com>
 <5748f659-4063-0e18-c5d4-941a863d0d93@intel.com>
In-Reply-To: <5748f659-4063-0e18-c5d4-941a863d0d93@intel.com>
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Arnd, is this a good candidate for 6.7? Though old, the patch applies
cleanly on 6.6-rc4. I can re-send this one if you would prefer that.

On 8/3/2023 2:44 PM, Sohil Mehta wrote:
> On 7/10/2023 11:51 AM, Sohil Mehta wrote:
>> commit 'be65de6b03aa ("fs: Remove dcookies support")' removed the
>> syscall definition for lookup_dcookie.  However, syscall tables still
>> point to the old sys_lookup_dcookie() definition. Update syscall tables
>> of all architectures to directly point to sys_ni_syscall() instead.
>>
>> Signed-off-by: Sohil Mehta <sohil.mehta@intel.com>
>> Reviewed-by: Randy Dunlap <rdunlap@infradead.org>
>> Acked-by: Namhyung Kim <namhyung@kernel.org> # for perf
> 
> The patch has received a couple of additional Acks.
> 

Namely,

Acked-by: Geert Uytterhoeven <geert@linux-m68k.org>
Acked-by: Russell King (Oracle) <rmk+kernel@armlinux.org.uk>

> Does this seem like a valuable cleanup? If so, should it go through the
> asm-generic tree?
> 

The main motivation here is to make readers aware upfront (via the
syscall table itself) that no implementation exists for lookup_dcookie
instead of them searching for one and realizing the same. The syscall
tables do something similar for _sysctl().

Please let me know if this change seems unnecessary. I can drop the
annoying pings in that case.

Thanks,
Sohil