Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S933268Ab2JWRac (ORCPT ); Tue, 23 Oct 2012 13:30:32 -0400 Received: from usmamail.tilera.com ([12.216.194.151]:25501 "EHLO USMAMAIL.TILERA.COM" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1755485Ab2JWRaa (ORCPT ); Tue, 23 Oct 2012 13:30:30 -0400 Message-ID: <5086D432.4070008@tilera.com> Date: Tue, 23 Oct 2012 13:30:26 -0400 From: Chris Metcalf User-Agent: Mozilla/5.0 (Windows NT 6.1; WOW64; rv:16.0) Gecko/20121010 Thunderbird/16.0.1 MIME-Version: 1.0 To: Al Viro CC: , , Linus Torvalds , Catalin Marinas Subject: Re: [PATCH] tile: support GENERIC_KERNEL_THREAD and GENERIC_KERNEL_EXECVE References: <20121016223508.GR2616@ZenIV.linux.org.uk> <201210192041.q9JKf7jD003998@farm-0010.internal.tilera.com> <20121019213548.GR2616@ZenIV.linux.org.uk> <5082A1F1.3080303@tilera.com> <20121020153401.GT2616@ZenIV.linux.org.uk> <20121020171643.GU2616@ZenIV.linux.org.uk> In-Reply-To: <20121020171643.GU2616@ZenIV.linux.org.uk> X-Enigmail-Version: 1.4.5 Content-Type: text/plain; charset="ISO-8859-1" Content-Transfer-Encoding: 7bit Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Content-Length: 3736 Lines: 69 On 10/20/2012 1:16 PM, Al Viro wrote: > On Sat, Oct 20, 2012 at 04:34:01PM +0100, Al Viro wrote: >> On Sat, Oct 20, 2012 at 09:06:57AM -0400, Chris Metcalf wrote: >>> First, the compat_sys_execve() declaration provided in >>> arch/tile/include/asm/compat.h isn't right, so I deleted that (you had only >>> deleted the PTREGS_SYSCALL trampoline declaration, _compat_sys_execve). >>> >>> However, then arch/tile/kernel/compat.c failed to build, because >>> is included before , and >>> provides __ARCH_WANT_SYS_EXECVE, and so we end up with no declaration at >>> all for compat_sys_execve. For most platforms this is no big deal, but on >>> tile we use the __SYSCALL #define to provide the actual syscall table, and >>> for that to work we need a declaration in scope for each syscall at the >>> time we create the table. >>> >>> The best solution seems likely to be to copy the other place in >>> where we need to do something configurable (that is, >>> CONFIG_ARCH_WANT_OLD_COMPAT_IPC), and just convert __ARCH_WANT_SYS_EXECVE >>> to be a Kconfig option. >> Frankly, I hope to get rid of the damn thing completely. By now we have >> at least some variant of execve conversions for just about everything; >> I certainly hope that by the beginning of the next cycle we'll have it >> defined on everything. And put unconditional declarations in syscalls.h >> and compat.h >> >> Actually, we can make the declaration in linux/compat.h unconditional >> right now. The only obstacle is the situation on arm64; there the mainline >> has C variant of that sucker (with struct pt_regs * in arguments) in >> arch/arm64/kernel/sys_compat.c. So we could ask Linus to pull >> git://git.kernel.org/pub/scm/linux/kernel/git/cmarinas/linux-aarch64 execve >> and then do the following in one patch: >> introduce current_pt_regs() on tile (from your commit) >> get rid of pt_regs * argument in tile compat_sys_execve(), making it >> use current_pt_regs(); kill its wrapper >> kill the declarations of compat_sys_execve()/_compat_sys_execve() >> in tile asm/compat.h >> make declaration in linux/compat.h unconditional >> Note that this does *not* depend on kernel_thread/kernel_execve patch - >> kernel_execve() is never going to hit compat_sys_execve(), since it's >> only called from kernel threads and those are not going to be 32bit. >> After that we can do kernel_thread/kernel_execve commit and >> sys_execve() conversion with nothing outside of arch/tile touched. > Another possible variant is for you to merge that branch from arm64 tree > (only 3 commits it it) and then do as described above. I.e. on top of > that apply the thing below, followed by your kernel_thread()/kernel_execve() > patch (sans current_pt_regs() part), followed by obviously massaged parts > of generic sys_execve for tile patch I've sent. FWIW, I've put the > whole series (based at the end of arm64 branch) in signal.git#arch-tile. > Comments? I fetched the series from your arch-tile branch and built it, and it works fine. It looks good from my inspection: Acked-by: Chris Metcalf As you had suggested in an earlier email, I went ahead and eliminated the special pt_regs handling for sigaltstack, rt_sigreturn, and clone. (Also a tilepro-specific syscall that was also using PTREG_SYSCALL.) I'll send it separately and you can include it in your tree if you like. -- Chris Metcalf, Tilera Corp. http://www.tilera.com -- To unsubscribe from this list: send the line "unsubscribe linux-kernel" in the body of a message to majordomo@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/