From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: from s3.sipsolutions.net ([2a01:4f8:191:4433::2] helo=sipsolutions.net) by desiato.infradead.org with esmtps (Exim 4.94 #2 (Red Hat Linux)) id 1lHTw1-005VUi-5d for linux-um@lists.infradead.org; Wed, 03 Mar 2021 16:01:17 +0000 From: Benjamin Berg Subject: [PATCH 21/27] um: Add UML_SECCOMP configuration option Date: Wed, 3 Mar 2021 16:55:17 +0100 Message-Id: <20210303155523.124277-22-benjamin@sipsolutions.net> In-Reply-To: <20210303155523.124277-1-benjamin@sipsolutions.net> References: <20210303155523.124277-1-benjamin@sipsolutions.net> MIME-Version: 1.0 List-Id: List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Content-Type: text/plain; charset="us-ascii" Content-Transfer-Encoding: 7bit Sender: "linux-um" Errors-To: linux-um-bounces+geert=linux-m68k.org@lists.infradead.org To: linux-um@lists.infradead.org Cc: Benjamin Berg Add the UML_SECCOMP configuration options. The next commits will add the support itself in smaller chunks. Only x86_64 will be supported for now. Signed-off-by: Benjamin Berg --- arch/um/Kconfig | 19 +++++++++++++++++++ 1 file changed, 19 insertions(+) diff --git a/arch/um/Kconfig b/arch/um/Kconfig index c3030db3325f..769bc770c5fa 100644 --- a/arch/um/Kconfig +++ b/arch/um/Kconfig @@ -188,6 +188,25 @@ config UML_TIME_TRAVEL_SUPPORT It is safe to say Y, but you probably don't need this. +config UML_SECCOMP + bool "seccomp based process tracing" + default n + depends on 64BIT + help + Enable this option will enable seccomp based tracing of processes. + + UML must call syscalls from within the userspace processes when + mapping physical memory in response to page faults. Using seccomp + based tracing permits delaying these host syscalls until userspace + processes are resumed in order to run a task, thereby avoiding + overhead for the host by saving context switches. + + This feature speeds up e.g. fork() heavy workloads considerably. + However, the current implementation is not safe as userspace + processes can trigger any syscall to the host OS. + + If in doubt say N, as the feature has security implications. + endmenu source "arch/um/drivers/Kconfig" -- 2.29.2 _______________________________________________ linux-um mailing list linux-um@lists.infradead.org http://lists.infradead.org/mailman/listinfo/linux-um