linux-kernel - Re: [C/R ARM][PATCH 1/3] ARM: Rudimentary syscall interfaces

lists.openwall.net		lists / announce owl-users owl-dev john-users john-dev passwdqc-users yescrypt popa3d-users / oss-security kernel-hardening musl sabotage tlsify passwords / crypt-dev xvendor / Bugtraq Full-Disclosure linux-kernel linux-netdev linux-ext4 linux-hardening linux-cve-announce PHC
Open Source and information security mailing list archives

Hash Suite: Windows password security audit tool. GUI, reports in PDF.

[<prev] [next>] [<thread-prev] [thread-next>] [day] [month] [year] [list]

Message-ID: <20100323205342.GA19572@n2100.arm.linux.org.uk>
Date:	Tue, 23 Mar 2010 20:53:42 +0000
From:	Russell King - ARM Linux <linux@....linux.org.uk>
To:	Christoffer Dall <christofferdall@...istofferdall.dk>
Cc:	containers <containers@...ts.linux-foundation.org>,
	linux-arm-kernel <linux-arm-kernel@...ts.infradead.org>,
	linux-kernel <linux-kernel@...r.kernel.org>,
	Roland McGrath <roland@...hat.com>
Subject: Re: [C/R ARM][PATCH 1/3] ARM: Rudimentary syscall interfaces

On Sun, Mar 21, 2010 at 09:06:03PM -0400, Christoffer Dall wrote:
> This small commit introduces a global state of system calls for ARM
> making it possible for a debugger or checkpointing to gain information
> about another process' state with respect to system calls.

I don't particularly like the idea that we always store the syscall
number to memory for every system call, whether the stored version is
used or not.

Since ARM caches are generally not write allocate, this means mostly
write-only variables can have a higher than expected expense.

Is there not some thread flag which can be checked to see if we need to
store the syscall number?
--
To unsubscribe from this list: send the line "unsubscribe linux-kernel" in
the body of a message to majordomo@...r.kernel.org
More majordomo info at  http://vger.kernel.org/majordomo-info.html
Please read the FAQ at  http://www.tux.org/lkml/