From: Stas Sergeev <stsp@list.ru> To: Ricardo Neri <ricardo.neri-calderon@linux.intel.com> Cc: Andy Lutomirski <luto@amacapital.net>, Ingo Molnar <mingo@redhat.com>, Thomas Gleixner <tglx@linutronix.de>, "H. Peter Anvin" <hpa@zytor.com>, Andy Lutomirski <luto@kernel.org>, Borislav Petkov <bp@suse.de>, Peter Zijlstra <peterz@infradead.org>, Andrew Morton <akpm@linux-foundation.org>, Brian Gerst <brgerst@gmail.com>, Chris Metcalf <cmetcalf@mellanox.com>, Dave Hansen <dave.hansen@linux.intel.com>, Paolo Bonzini <pbonzini@redhat.com>, Liang Z Li <liang.z.li@intel.com>, Masami Hiramatsu <mhiramat@kernel.org>, Huang Rui <ray.huang@amd.com>, Jiri Slaby <jslaby@suse.cz>, Jonathan Corbet <corbet@lwn.net>, "Michael S. Tsirkin" <mst@redhat.com>, Paul Gortmaker <paul.gortmaker@windriver.com>, Vlastimil Babka <vbabka@suse.cz>, Chen Yucong <slaoub@gmail.com>, Alexandre Julliard <julliard@winehq.org>, Fenghua Yu <fenghua.yu@intel.com>, "Ravi V. Shankar" <ravi.v.shankar@intel.com>, Shuah Khan <shuah@kernel.org>, "linux-kernel@vger.kernel.org" <linux-kernel@vger.kernel.org>, X86 ML <x86@kernel.org>, linux-msdos@vger.kernel.org, wine-devel@winehq.org Subject: Re: [v6 PATCH 00/21] x86: Enable User-Mode Instruction Prevention Date: Tue, 28 Mar 2017 12:38:24 +0300 [thread overview] Message-ID: <cc490254-9c0b-e55e-6228-ad5e1f365123@list.ru> (raw) In-Reply-To: <1490658399.2647.14.camel@ranerica-desktop> 28.03.2017 02:46, Ricardo Neri пишет: > On Tue, 2017-03-14 at 00:25 +0300, Stas Sergeev wrote: >> 11.03.2017 02:59, Ricardo Neri пишет: >>> On Fri, 2017-03-10 at 14:33 +0300, Stas Sergeev wrote: >>> >>>> Why would you need one? >>>> Or do you really want to allow these instructions >>>> in v86 by the means of emulation? If so - this wasn't >>>> clearly stated in the patch description, neither it was >>>> properly discussed, it seems. >>> It str and sldt can be emulated in vm86 but as Andy mention, the >>> behavior sould be the same with and without emulation. >> Why would you do that? >> I looked up the dosemu2 CPU simulator code that >> is used under x86-64. It says this: > Stas, I apologize for the delayed reply; I missed your e-mail. >> It only implements smsw. >> So maybe you can make your code much >> simpler and remove the unneeded emulation? >> Same is for prot mode. > Do you mean the unneeded emulation for SLDT and STR? Not quite, I meant also sgdt and sidt in vm86. Yes that it will be a somewhat "incompatible" change, but if there is nothing to stay compatible with, then why to worry? Probably you could also remove the sldt and str emulation for protected mode, because, as I understand from this thread, wine does not need those. Note that these days dosemu2 uses v86 mode set up under kvm rather than vm86(). Your patches affect that the same way as they do for vm86() syscall, or can there be some differences? Or should the UMIP be enabled under kvm by hands? >> You know the wine's >> requirements now - they are very small. And >> dosemu doesn't need anything at all but smsw. >> And even smsw is very rare. > But emulation is still needed for SMSW, right? Likely so. If you want, I can enable the logging of this command and see if it is used by some of the DOS programs I have. But at least dosemu implements it, so probably it is needed. Of course if it is used by one of 100 DOS progs, then there is an option to just add its support to dosemu2 and pretend the compatibility problems did not exist. :) So, if this can be an option, I can do the tests to estimate its usage.
WARNING: multiple messages have this Message-ID (diff)
From: Stas Sergeev <stsp@list.ru> To: Ricardo Neri <ricardo.neri-calderon@linux.intel.com> Cc: Andy Lutomirski <luto@amacapital.net>, Ingo Molnar <mingo@redhat.com>, Thomas Gleixner <tglx@linutronix.de>, "H. Peter Anvin" <hpa@zytor.com>, Andy Lutomirski <luto@kernel.org>, Borislav Petkov <bp@suse.de>, Peter Zijlstra <peterz@infradead.org>, Andrew Morton <akpm@linux-foundation.org>, Brian Gerst <brgerst@gmail.com>, Chris Metcalf <cmetcalf@mellanox.com>, Dave Hansen <dave.hansen@linux.intel.com>, Paolo Bonzini <pbonzini@redhat.com>, Liang Z Li <liang.z.li@intel.com>, Masami Hiramatsu <mhiramat@kernel.org>, Huang Rui <ray.huang@amd.com>, Jiri Slaby <jslaby@suse.cz>, Jonathan Corbet <corbet@lwn.net>, "Michael S. Tsirkin" <mst@redhat.com>, Paul Gortmaker <paul.gortmaker@windriver.com>, Vlastimil Babka <vbabka@suse.cz>, Chen Yucong <> Subject: Re: [v6 PATCH 00/21] x86: Enable User-Mode Instruction Prevention Date: Tue, 28 Mar 2017 12:38:24 +0300 [thread overview] Message-ID: <cc490254-9c0b-e55e-6228-ad5e1f365123@list.ru> (raw) In-Reply-To: <1490658399.2647.14.camel@ranerica-desktop> 28.03.2017 02:46, Ricardo Neri пишет: > On Tue, 2017-03-14 at 00:25 +0300, Stas Sergeev wrote: >> 11.03.2017 02:59, Ricardo Neri пишет: >>> On Fri, 2017-03-10 at 14:33 +0300, Stas Sergeev wrote: >>> >>>> Why would you need one? >>>> Or do you really want to allow these instructions >>>> in v86 by the means of emulation? If so - this wasn't >>>> clearly stated in the patch description, neither it was >>>> properly discussed, it seems. >>> It str and sldt can be emulated in vm86 but as Andy mention, the >>> behavior sould be the same with and without emulation. >> Why would you do that? >> I looked up the dosemu2 CPU simulator code that >> is used under x86-64. It says this: > Stas, I apologize for the delayed reply; I missed your e-mail. >> It only implements smsw. >> So maybe you can make your code much >> simpler and remove the unneeded emulation? >> Same is for prot mode. > Do you mean the unneeded emulation for SLDT and STR? Not quite, I meant also sgdt and sidt in vm86. Yes that it will be a somewhat "incompatible" change, but if there is nothing to stay compatible with, then why to worry? Probably you could also remove the sldt and str emulation for protected mode, because, as I understand from this thread, wine does not need those. Note that these days dosemu2 uses v86 mode set up under kvm rather than vm86(). Your patches affect that the same way as they do for vm86() syscall, or can there be some differences? Or should the UMIP be enabled under kvm by hands? >> You know the wine's >> requirements now - they are very small. And >> dosemu doesn't need anything at all but smsw. >> And even smsw is very rare. > But emulation is still needed for SMSW, right? Likely so. If you want, I can enable the logging of this command and see if it is used by some of the DOS programs I have. But at least dosemu implements it, so probably it is needed. Of course if it is used by one of 100 DOS progs, then there is an option to just add its support to dosemu2 and pretend the compatibility problems did not exist. :) So, if this can be an option, I can do the tests to estimate its usage.
next prev parent reply other threads:[~2017-03-28 9:39 UTC|newest] Thread overview: 222+ messages / expand[flat|nested] mbox.gz Atom feed top 2017-03-08 0:32 [v6 PATCH 00/21] x86: Enable User-Mode Instruction Prevention Ricardo Neri 2017-03-08 0:32 ` Ricardo Neri 2017-03-08 0:32 ` [v6 PATCH 01/21] x86/mpx: Use signed variables to compute effective addresses Ricardo Neri 2017-03-08 0:32 ` Ricardo Neri 2017-04-11 21:56 ` Borislav Petkov 2017-04-11 21:56 ` Borislav Petkov 2017-04-26 1:40 ` Ricardo Neri 2017-04-26 1:40 ` Ricardo Neri 2017-03-08 0:32 ` [v6 PATCH 02/21] x86/mpx: Do not use SIB index if index points to R/ESP Ricardo Neri 2017-03-08 0:32 ` Ricardo Neri 2017-04-11 11:31 ` Borislav Petkov 2017-04-11 11:31 ` Borislav Petkov 2017-04-26 1:39 ` Ricardo Neri 2017-04-26 1:39 ` Ricardo Neri 2017-03-08 0:32 ` [v6 PATCH 03/21] x86/mpx: Do not use R/EBP as base in the SIB byte with Mod = 0 Ricardo Neri 2017-03-08 0:32 ` Ricardo Neri 2017-04-11 22:08 ` Borislav Petkov 2017-04-11 22:08 ` Borislav Petkov 2017-04-26 2:04 ` Ricardo Neri 2017-04-26 2:04 ` Ricardo Neri 2017-04-26 8:05 ` Borislav Petkov 2017-04-26 8:05 ` Borislav Petkov 2017-04-27 22:49 ` Ricardo Neri 2017-04-27 22:49 ` Ricardo Neri 2017-03-08 0:32 ` [v6 PATCH 04/21] x86/mpx, x86/insn: Relocate insn util functions to a new insn-kernel Ricardo Neri 2017-03-08 0:32 ` Ricardo Neri 2017-04-12 10:03 ` Borislav Petkov 2017-04-12 10:03 ` Borislav Petkov 2017-04-26 2:05 ` Ricardo Neri 2017-04-26 2:05 ` Ricardo Neri 2017-03-08 0:32 ` [v6 PATCH 05/21] x86/insn-eval: Add utility functions to get register offsets Ricardo Neri 2017-03-08 0:32 ` Ricardo Neri 2017-04-12 16:28 ` Borislav Petkov 2017-04-12 16:28 ` Borislav Petkov 2017-04-26 18:13 ` Ricardo Neri 2017-04-26 18:13 ` Ricardo Neri 2017-04-28 10:40 ` Borislav Petkov 2017-04-28 10:40 ` Borislav Petkov 2017-03-08 0:32 ` [v6 PATCH 06/21] x86/insn-eval: Add utility functions to get segment selector Ricardo Neri 2017-03-08 0:32 ` Ricardo Neri 2017-04-18 9:42 ` Borislav Petkov 2017-04-18 9:42 ` Borislav Petkov 2017-04-26 20:44 ` Ricardo Neri 2017-04-26 20:44 ` Ricardo Neri 2017-04-26 20:47 ` Ricardo Neri 2017-04-26 20:47 ` Ricardo Neri 2017-04-30 17:15 ` Borislav Petkov 2017-04-30 17:15 ` Borislav Petkov 2017-05-05 18:31 ` Ricardo Neri 2017-05-05 18:31 ` Ricardo Neri 2017-03-08 0:32 ` [v6 PATCH 07/21] x86/insn-eval: Add utility function to get segment descriptor Ricardo Neri 2017-03-08 0:32 ` Ricardo Neri 2017-04-19 10:26 ` Borislav Petkov 2017-04-19 10:26 ` Borislav Petkov 2017-04-26 21:51 ` Ricardo Neri 2017-04-26 21:51 ` Ricardo Neri 2017-05-04 11:02 ` Borislav Petkov 2017-05-04 11:02 ` Borislav Petkov 2017-05-12 2:13 ` Ricardo Neri 2017-05-12 2:13 ` Ricardo Neri 2017-05-15 17:27 ` Borislav Petkov 2017-05-15 17:27 ` Borislav Petkov 2017-03-08 0:32 ` [v6 PATCH 08/21] x86/insn-eval: Add utility function to get segment descriptor base address Ricardo Neri 2017-03-08 0:32 ` Ricardo Neri 2017-04-20 8:25 ` Borislav Petkov 2017-04-20 8:25 ` Borislav Petkov 2017-04-26 22:37 ` Ricardo Neri 2017-04-26 22:37 ` Ricardo Neri 2017-05-05 17:19 ` Borislav Petkov 2017-05-05 17:19 ` Borislav Petkov 2017-05-12 2:09 ` Ricardo Neri 2017-05-12 2:09 ` Ricardo Neri 2017-04-26 22:52 ` Ricardo Neri 2017-04-26 22:52 ` Ricardo Neri 2017-05-05 17:28 ` Borislav Petkov 2017-05-05 17:28 ` Borislav Petkov 2017-05-12 2:06 ` Ricardo Neri 2017-05-12 2:06 ` Ricardo Neri 2017-03-08 0:32 ` [v6 PATCH 09/21] x86/insn-eval: Add functions to get default operand and address sizes Ricardo Neri 2017-03-08 0:32 ` Ricardo Neri 2017-04-20 13:06 ` Borislav Petkov 2017-04-20 13:06 ` Borislav Petkov 2017-04-27 1:07 ` Ricardo Neri 2017-04-27 1:07 ` Ricardo Neri 2017-03-08 0:32 ` [v6 PATCH 10/21] x86/insn-eval: Do not use R/EBP as base if mod in ModRM is zero Ricardo Neri 2017-03-08 0:32 ` Ricardo Neri 2017-04-21 10:52 ` Borislav Petkov 2017-04-21 10:52 ` Borislav Petkov 2017-04-27 1:29 ` Ricardo Neri 2017-04-27 1:29 ` Ricardo Neri 2017-05-07 17:20 ` Borislav Petkov 2017-05-07 17:20 ` Borislav Petkov 2017-05-12 1:57 ` Ricardo Neri 2017-05-12 1:57 ` Ricardo Neri 2017-03-08 0:32 ` [v6 PATCH 11/21] insn/eval: Incorporate segment base in address computation Ricardo Neri 2017-03-08 0:32 ` Ricardo Neri 2017-04-21 14:55 ` Borislav Petkov 2017-04-21 14:55 ` Borislav Petkov 2017-04-27 1:31 ` Ricardo Neri 2017-04-27 1:31 ` Ricardo Neri 2017-03-08 0:32 ` [v6 PATCH 12/21] x86/insn: Support both signed 32-bit and 64-bit effective addresses Ricardo Neri 2017-03-08 0:32 ` Ricardo Neri 2017-04-25 13:51 ` Borislav Petkov 2017-04-25 13:51 ` Borislav Petkov 2017-04-27 3:33 ` Ricardo Neri 2017-04-27 3:33 ` Ricardo Neri 2017-05-08 11:42 ` Borislav Petkov 2017-05-08 11:42 ` Borislav Petkov 2017-05-12 1:55 ` Ricardo Neri 2017-05-12 1:55 ` Ricardo Neri 2017-03-08 0:32 ` [v6 PATCH 13/21] x86/insn-eval: Add support to resolve 16-bit addressing encodings Ricardo Neri 2017-03-08 0:32 ` Ricardo Neri 2017-03-08 0:32 ` [v6 PATCH 14/21] x86/insn-eval: Add wrapper function for 16-bit and 32-bit address encodings Ricardo Neri 2017-03-08 0:32 ` Ricardo Neri 2017-03-08 0:32 ` [v6 PATCH 15/21] x86/mm: Relocate page fault error codes to traps.h Ricardo Neri 2017-03-08 0:32 ` Ricardo Neri 2017-03-08 16:08 ` Andy Lutomirski 2017-03-08 16:08 ` Andy Lutomirski 2017-03-08 0:32 ` [v6 PATCH 16/21] x86/cpufeature: Add User-Mode Instruction Prevention definitions Ricardo Neri 2017-03-08 0:32 ` Ricardo Neri 2017-03-08 0:32 ` [v6 PATCH 17/21] x86: Add emulation code for UMIP instructions Ricardo Neri 2017-03-08 0:32 ` Ricardo Neri 2017-03-08 0:32 ` [v6 PATCH 18/21] x86/umip: Force a page fault when unable to copy emulated result to user Ricardo Neri 2017-03-08 0:32 ` Ricardo Neri 2017-03-08 0:32 ` [v6 PATCH 19/21] x86/traps: Fixup general protection faults caused by UMIP Ricardo Neri 2017-03-08 0:32 ` Ricardo Neri 2017-03-08 15:54 ` Andy Lutomirski 2017-03-08 15:54 ` Andy Lutomirski 2017-03-08 0:32 ` [v6 PATCH 20/21] x86: Enable User-Mode Instruction Prevention Ricardo Neri 2017-03-08 0:32 ` Ricardo Neri 2017-03-08 0:32 ` [v6 PATCH 21/21] selftests/x86: Add tests for " Ricardo Neri 2017-03-08 0:32 ` Ricardo Neri 2017-03-08 15:56 ` Andy Lutomirski 2017-03-08 15:56 ` Andy Lutomirski 2017-03-10 23:38 ` Ricardo Neri 2017-03-10 23:38 ` Ricardo Neri 2017-03-08 14:08 ` [v6 PATCH 00/21] x86: Enable " Stas Sergeev 2017-03-08 14:08 ` Stas Sergeev 2017-03-08 16:06 ` Andy Lutomirski 2017-03-08 16:06 ` Andy Lutomirski 2017-03-08 16:29 ` Stas Sergeev 2017-03-08 16:29 ` Stas Sergeev 2017-03-08 16:46 ` Andy Lutomirski 2017-03-08 16:46 ` Andy Lutomirski 2017-03-08 16:53 ` Stas Sergeev 2017-03-08 16:53 ` Stas Sergeev 2017-03-09 1:11 ` Ricardo Neri 2017-03-09 1:11 ` Ricardo Neri 2017-03-09 22:05 ` Stas Sergeev 2017-03-09 22:05 ` Stas Sergeev 2017-03-10 2:41 ` Andy Lutomirski 2017-03-10 2:41 ` Andy Lutomirski 2017-03-10 10:30 ` Stas Sergeev 2017-03-10 10:30 ` Stas Sergeev 2017-03-10 21:04 ` Andy Lutomirski 2017-03-10 21:04 ` Andy Lutomirski 2017-03-10 21:37 ` Stas Sergeev 2017-03-10 21:37 ` Stas Sergeev 2017-03-09 1:15 ` Ricardo Neri 2017-03-09 1:15 ` Ricardo Neri 2017-03-09 22:10 ` Stas Sergeev 2017-03-09 22:10 ` Stas Sergeev 2017-03-10 2:39 ` Andy Lutomirski 2017-03-10 2:39 ` Andy Lutomirski 2017-03-10 11:33 ` Stas Sergeev 2017-03-10 11:33 ` Stas Sergeev 2017-03-10 14:17 ` Andy Lutomirski 2017-03-10 14:17 ` Andy Lutomirski 2017-03-11 1:22 ` Ricardo Neri 2017-03-11 1:22 ` Ricardo Neri 2017-03-10 23:59 ` Ricardo Neri 2017-03-10 23:59 ` Ricardo Neri 2017-03-13 21:25 ` Stas Sergeev 2017-03-13 21:25 ` Stas Sergeev 2017-03-27 23:46 ` Ricardo Neri 2017-03-27 23:46 ` Ricardo Neri 2017-03-28 9:38 ` Stas Sergeev [this message] 2017-03-28 9:38 ` Stas Sergeev 2017-03-29 4:38 ` Ricardo Neri 2017-03-29 4:38 ` Ricardo Neri 2017-03-29 20:55 ` Stas Sergeev 2017-03-29 20:55 ` Stas Sergeev 2017-03-30 5:14 ` Ricardo Neri 2017-03-30 5:14 ` Ricardo Neri 2017-03-30 10:10 ` Stas Sergeev 2017-03-30 10:10 ` Stas Sergeev 2017-03-31 1:33 ` Ricardo Neri 2017-03-31 1:33 ` Ricardo Neri 2017-03-31 14:11 ` Alexandre Julliard 2017-03-31 14:11 ` Alexandre Julliard 2017-03-31 21:26 ` Stas Sergeev 2017-03-31 21:26 ` Stas Sergeev 2017-04-01 2:18 ` Andy Lutomirski 2017-04-01 2:18 ` Andy Lutomirski 2017-04-04 2:02 ` Ricardo Neri 2017-04-04 2:02 ` Ricardo Neri 2017-04-04 6:08 ` Alexandre Julliard 2017-04-04 6:08 ` Alexandre Julliard 2017-04-01 13:08 ` Stas Sergeev 2017-04-01 13:08 ` Stas Sergeev 2017-04-01 17:49 ` H. Peter Anvin 2017-04-01 17:49 ` H. Peter Anvin 2017-04-02 15:52 ` Andy Lutomirski 2017-04-04 9:59 ` Stas Sergeev 2017-04-04 2:05 ` Ricardo Neri 2017-04-04 2:05 ` Ricardo Neri 2017-04-04 8:03 ` Stas Sergeev 2017-04-04 8:03 ` Stas Sergeev 2017-03-10 23:58 ` Ricardo Neri 2017-03-10 23:58 ` Ricardo Neri 2017-03-09 0:46 ` Ricardo Neri 2017-03-09 0:46 ` Ricardo Neri 2017-03-09 22:01 ` Stas Sergeev 2017-03-09 22:01 ` Stas Sergeev 2017-03-10 23:47 ` Ricardo Neri 2017-03-10 23:47 ` Ricardo Neri 2017-03-10 23:58 ` Stas Sergeev 2017-03-10 23:58 ` Stas Sergeev 2017-03-11 0:13 ` Ricardo Neri 2017-03-11 0:13 ` Ricardo Neri 2017-03-08 16:07 ` Andy Lutomirski 2017-03-08 16:07 ` Andy Lutomirski
Reply instructions: You may reply publicly to this message via plain-text email using any one of the following methods: * Save the following mbox file, import it into your mail client, and reply-to-all from there: mbox Avoid top-posting and favor interleaved quoting: https://en.wikipedia.org/wiki/Posting_style#Interleaved_style * Reply using the --to, --cc, and --in-reply-to switches of git-send-email(1): git send-email \ --in-reply-to=cc490254-9c0b-e55e-6228-ad5e1f365123@list.ru \ --to=stsp@list.ru \ --cc=akpm@linux-foundation.org \ --cc=bp@suse.de \ --cc=brgerst@gmail.com \ --cc=cmetcalf@mellanox.com \ --cc=corbet@lwn.net \ --cc=dave.hansen@linux.intel.com \ --cc=fenghua.yu@intel.com \ --cc=hpa@zytor.com \ --cc=jslaby@suse.cz \ --cc=julliard@winehq.org \ --cc=liang.z.li@intel.com \ --cc=linux-kernel@vger.kernel.org \ --cc=linux-msdos@vger.kernel.org \ --cc=luto@amacapital.net \ --cc=luto@kernel.org \ --cc=mhiramat@kernel.org \ --cc=mingo@redhat.com \ --cc=mst@redhat.com \ --cc=paul.gortmaker@windriver.com \ --cc=pbonzini@redhat.com \ --cc=peterz@infradead.org \ --cc=ravi.v.shankar@intel.com \ --cc=ray.huang@amd.com \ --cc=ricardo.neri-calderon@linux.intel.com \ --cc=shuah@kernel.org \ --cc=slaoub@gmail.com \ --cc=tglx@linutronix.de \ --cc=vbabka@suse.cz \ --cc=wine-devel@winehq.org \ --cc=x86@kernel.org \ /path/to/YOUR_REPLY https://kernel.org/pub/software/scm/git/docs/git-send-email.html * If your mail client supports setting the In-Reply-To header via mailto: links, try the mailto: linkBe sure your reply has a Subject: header at the top and a blank line before the message body.
This is an external index of several public inboxes, see mirroring instructions on how to clone and mirror all data and code used by this external index.