From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from smtp-4.orcon.net.nz (smtp-4.orcon.net.nz [60.234.4.59]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by smtp.subspace.kernel.org (Postfix) with ESMTPS id 28DB8369982; Tue, 24 Feb 2026 09:32:42 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.client-ip=60.234.4.59 ARC-Seal:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1771925564; cv=none; b=JuQ9fS/fP3qkEq1VND7rUtiIqCrLRf3Dk7cijIGIiicRJUhQTo8Eegw7NK1QR3TjDkzyj5aMMmE6YE7094haOoZuFi4O7kgEJRTlsUNYOoIODY8QFD9WqEe6EEDub325w3KcqOo6nxRtOrPxvUpNVt1+5Isi4ij3cEsIvReNobo= ARC-Message-Signature:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1771925564; c=relaxed/simple; bh=IOJgxaam+EX1KGnYY0VduJPKBbOwGW6h09urZlUbJOQ=; h=Date:From:To:Cc:Subject:Message-ID:References:MIME-Version: Content-Type:Content-Disposition:In-Reply-To; b=Be4sov9JBvhfOw+j3sE3JPaa6Dzby+L6Nh+Dlb5mmeO7Mhd50qwDLKwfj2b4p9MhZ2ts3aDdaZAB4jhtpaLrBAaPnAXYeZFR1bmdJBpdbd8UmREgrNPQwBz3v3qI/u18m6ooi9pOS7pgNgcEgqyaN0TM1MI+r8vohyjAJ3bm0bw= ARC-Authentication-Results:i=1; smtp.subspace.kernel.org; dmarc=pass (p=none dis=none) header.from=orcon.net.nz; spf=pass smtp.mailfrom=orcon.net.nz; arc=none smtp.client-ip=60.234.4.59 Authentication-Results: smtp.subspace.kernel.org; dmarc=pass (p=none dis=none) header.from=orcon.net.nz Authentication-Results: smtp.subspace.kernel.org; spf=pass smtp.mailfrom=orcon.net.nz Received: from [121.99.247.178] (port=50414 helo=creeky) by smtp-4.orcon.net.nz with esmtpa (Exim 4.90_1) (envelope-from ) id 1vuoAV-0002yB-L4; Tue, 24 Feb 2026 21:53:24 +1300 Date: Tue, 24 Feb 2026 21:53:15 +1300 From: Michael Cree To: Magnus Lindholm Cc: richard.henderson@linaro.org, mattst88@gmail.com, linux-kernel@vger.kernel.org, linux-alpha@vger.kernel.org, corbet@lwn.net, linux-doc@vger.kernel.org, glaubitz@physik.fu-berlin.de, macro@orcam.me.uk, macro@redhat.com, ink@unseen.parts Subject: Re: [PATCH v2 0/1] alpha: add support for SECCOMP and SECCOMP_FILTER Message-ID: Mail-Followup-To: Michael Cree , Magnus Lindholm , richard.henderson@linaro.org, mattst88@gmail.com, linux-kernel@vger.kernel.org, linux-alpha@vger.kernel.org, corbet@lwn.net, linux-doc@vger.kernel.org, glaubitz@physik.fu-berlin.de, macro@orcam.me.uk, macro@redhat.com, ink@unseen.parts References: <20260220105757.25104-1-linmag7@gmail.com> Precedence: bulk X-Mailing-List: linux-doc@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <20260220105757.25104-1-linmag7@gmail.com> X-GeoIP: NZ X-Spam_score: -2.9 X-Spam_score_int: -28 X-Spam_bar: -- On Fri, Feb 20, 2026 at 11:50:09AM +0100, Magnus Lindholm wrote: > This patch adds SECCOMP and SECCOMP_FILTER support to the Alpha > architecture. > > The seccomp-bpf selftests exercise syscall tracing, restart, and signal > interaction paths that were previously untested on Alpha. To support > these, the ptrace/strace syscall path is updated to reliably distinguish > internal skip-dispatch from userspace invalid syscall numbers, ensuring > that syscall(-1) continues to return -ENOSYS with correct r0/a3 > semantics. > > Supporting seccomp also requires correct syscall restart handling when > ptrace and signal delivery are involved. The traced syscall entry path > now consistently tracks syscall state using r0, r1, and r2 while > preserving Alpha's a3-based error reporting ABI: > > - r1 holds the mutable "current" syscall number > - r2 preserves the original syscall number for restart > - r0 and r19 (a3) retain their traditional roles as return value and > error indicator > > This separation allows syscall restarts to be gated strictly on valid > ERESTART* return codes in the ptrace/strace paths and prevents > kernel-internal restart values from leaking into userspace. > > Alpha also lacked support for PTRACE_GETREGSET(NT_PRSTATUS), causing > ptrace-based seccomp tests to fail with -EIO. Minimal GETREGSET and > SETREGSET support is added to export struct pt_regs directly. > > With these changes applied, the seccomp-bpf and ptrace syscall selftests > (seccomp_bpf, extended for Alpha) pass reliably on Alpha systems. > > --- > Changes since v1: > - Update features documentation for seccomp-filter/alpha > Link: https://lore.kernel.org/linux-alpha/20260205133049.526-1-linmag7@gmail.com/T/#t > > Magnus Lindholm (1): > alpha: add support for SECCOMP and SECCOMP_FILTER > Passes the seccomp-bpf selftests and the live tests of Adrian's alpha-support branch of libseccomp on my ES45. Tested-by: Michael Cree Cheers, Michael.