From: "Li, Xin3" <xin3.li@intel.com>
To: "H. Peter Anvin" <hpa@zytor.com>,
"Hansen, Dave" <dave.hansen@intel.com>,
"tglx@linutronix.de" <tglx@linutronix.de>,
"mingo@redhat.com" <mingo@redhat.com>,
"bp@alien8.de" <bp@alien8.de>,
"peterz@infradead.org" <peterz@infradead.org>,
"dave.hansen@linux.intel.com" <dave.hansen@linux.intel.com>
Cc: "x86@kernel.org" <x86@kernel.org>,
"linux-kernel@vger.kernel.org" <linux-kernel@vger.kernel.org>
Subject: RE: the x86 sysret_rip test fails on the Intel FRED architecture
Date: Sun, 22 Jan 2023 08:22:39 +0000 [thread overview]
Message-ID: <SA1PR11MB67344F0957245A2BC8CA57B7A8CB9@SA1PR11MB6734.namprd11.prod.outlook.com> (raw)
In-Reply-To: <65D9F1DE-96D4-4CC7-A21C-A740B7DDE0C8@zytor.com>
> On January 21, 2023 8:34:09 PM PST, Dave Hansen <dave.hansen@intel.com>
> wrote:
> >On 1/21/23 19:38, Li, Xin3 wrote:
> >>> However, it doesn't seem to make sense to do so to me. The current
> >>> behavior is much more of an artifact than desired behavior.
> >> We kind of have an agreement that %r11 = %flags after returning from the
> kernel.
> >>
> >> And the question is, is it what we want?
> >
> >Can the selftest just set r11=rflags before the syscall? The old
> >syscall entry path will set r11=rflags. The FRED path won't touch it.
> >Either case will pass an r11==rflags check.
>
> That's a good idea.
The problem is where/how to set %r11 = %rflags in the test code.
The check happens in the USER1 signal handler, and we could set %r11
just before calling raise(SIGUSR1). However, the C library implementation
of raise() modifies %r11, thus we can't preserve %r11 until the SYSCALL
instruction. And the test still fails.
Thanks!
XIn
next prev parent reply other threads:[~2023-01-22 8:22 UTC|newest]
Thread overview: 88+ messages / expand[flat|nested] mbox.gz Atom feed top
[not found] <SA1PR11MB6734FA9139B9C9F6CC2ED123A8C59@SA1PR11MB6734.namprd11.prod.outlook.com>
2023-01-20 17:45 ` the x86 sysret_rip test fails on the Intel FRED architecture Dave Hansen
[not found] ` <eb81f7f2-d266-d999-b41a-e6eae086e731@citrix.com>
2023-01-20 20:50 ` H. Peter Anvin
2023-01-20 21:10 ` Andrew Cooper
2023-01-20 21:17 ` H. Peter Anvin
2023-01-20 21:29 ` Andrew Cooper
2023-01-21 4:59 ` H. Peter Anvin
2023-01-21 16:46 ` Dave Hansen
2023-01-21 21:47 ` Brian Gerst
2023-01-22 3:01 ` Li, Xin3
2023-01-22 3:28 ` H. Peter Anvin
2023-01-22 3:38 ` Li, Xin3
2023-01-22 4:34 ` Dave Hansen
2023-01-22 4:44 ` H. Peter Anvin
2023-01-22 8:22 ` Li, Xin3 [this message]
2023-01-22 8:54 ` Ammar Faizi
2023-01-22 9:40 ` H. Peter Anvin
2023-01-22 23:45 ` H. Peter Anvin
2023-01-23 9:02 ` Ammar Faizi
2023-01-23 19:43 ` H. Peter Anvin
2023-01-23 23:43 ` Ammar Faizi
2023-01-23 23:58 ` H. Peter Anvin
2023-01-24 0:26 ` [RFC PATCH v1 0/2] selftests/x86: sysret_rip update for FRED system Ammar Faizi
2023-01-24 0:26 ` [RFC PATCH v1 1/2] selftests/x86: sysret_rip: Handle syscall in a " Ammar Faizi
2023-01-24 1:40 ` H. Peter Anvin
2023-01-24 2:31 ` Ammar Faizi
2023-01-26 20:08 ` Ammar Faizi
2023-02-15 9:17 ` Andrew Cooper
2023-02-15 10:29 ` Andrew Cooper
2023-02-15 10:44 ` Ammar Faizi
2023-02-15 10:42 ` Ammar Faizi
2023-01-26 20:16 ` Ammar Faizi
2023-01-24 0:26 ` [RFC PATCH v1 2/2] selftests/x86: sysret_rip: Add more syscall tests with respect to `%rcx` and `%r11` Ammar Faizi
2023-01-23 23:53 ` the x86 sysret_rip test fails on the Intel FRED architecture Andrew Cooper
2023-01-24 0:01 ` H. Peter Anvin
2023-01-24 2:27 ` [RFC PATCH v2 0/2] selftests/x86: sysret_rip update for FRED system Ammar Faizi
2023-01-24 2:27 ` [RFC PATCH v2 1/2] selftests/x86: sysret_rip: Handle syscall in a " Ammar Faizi
2023-01-24 5:44 ` H. Peter Anvin
2023-01-24 2:27 ` [RFC PATCH v2 2/2] selftests/x86: sysret_rip: Add more syscall tests with respect to `%rcx` and `%r11` Ammar Faizi
2023-01-24 6:16 ` H. Peter Anvin
2023-01-24 6:41 ` Ammar Faizi
2023-01-24 6:47 ` Ammar Faizi
2023-01-24 9:07 ` H. Peter Anvin
2023-01-24 9:12 ` Ammar Faizi
2023-01-24 10:09 ` [RFC PATCH v3 0/2] selftests/x86: sysret_rip update for FRED system Ammar Faizi
2023-01-24 10:09 ` [RFC PATCH v3 1/2] selftests/x86: sysret_rip: Handle syscall in a " Ammar Faizi
2023-01-24 10:09 ` [RFC PATCH v3 2/2] selftests/x86: sysret_rip: Add more syscall tests with respect to `%rcx` and `%r11` Ammar Faizi
2023-01-24 20:59 ` H. Peter Anvin
2023-01-25 3:29 ` Ammar Faizi
2023-01-24 21:32 ` [RFC PATCH v3 0/2] selftests/x86: sysret_rip update for FRED system Li, Xin3
2023-01-24 21:37 ` H. Peter Anvin
2023-01-24 23:20 ` Li, Xin3
2023-01-25 3:27 ` Ammar Faizi
2023-01-24 21:51 ` Andrew Cooper
2023-01-24 23:58 ` Li, Xin3
2023-01-25 3:22 ` [RFC PATCH v4 0/2] sysret_rip update for the Intel FRED architecture Ammar Faizi
2023-01-25 3:22 ` [RFC PATCH v4 1/2] selftests/x86: sysret_rip: Handle syscall in a FRED system Ammar Faizi
2023-01-25 3:37 ` Ammar Faizi
2023-01-25 3:44 ` Ammar Faizi
2023-01-25 3:22 ` [RFC PATCH v4 2/2] selftests/x86: sysret_rip: Add more syscall tests with respect to `%rcx` and `%r11` Ammar Faizi
2023-01-25 3:49 ` [RFC PATCH v5 0/2] sysret_rip update for the Intel FRED architecture Ammar Faizi
2023-01-25 3:49 ` [RFC PATCH v5 1/2] selftests/x86: sysret_rip: Handle syscall in a FRED system Ammar Faizi
2023-01-25 8:39 ` H. Peter Anvin
2023-01-25 8:53 ` Ammar Faizi
2023-01-25 9:57 ` Ammar Faizi
2023-01-25 10:01 ` Ammar Faizi
2023-01-25 10:17 ` H. Peter Anvin
2023-01-25 11:37 ` Ammar Faizi
2023-01-25 17:25 ` H. Peter Anvin
2023-01-25 3:49 ` [RFC PATCH v5 2/2] selftests/x86: sysret_rip: Add more syscall tests with respect to `%rcx` and `%r11` Ammar Faizi
2023-01-25 8:22 ` [RFC PATCH v5 0/2] sysret_rip update for the Intel FRED architecture Li, Xin3
2023-01-25 8:32 ` Ammar Faizi
2023-01-25 17:07 ` Li, Xin3
2023-01-25 17:24 ` H. Peter Anvin
2023-01-25 17:41 ` Ammar Faizi
2023-01-25 17:48 ` Li, Xin3
2023-02-15 7:42 ` Li, Xin3
2023-02-15 7:51 ` Ammar Faizi
2023-02-18 4:27 ` Ammar Faizi
2023-02-18 4:51 ` H. Peter Anvin
2023-01-25 21:17 ` [RFC PATCH v6 0/3] " Ammar Faizi
2023-01-25 21:17 ` [RFC PATCH v6 1/3] selftests/x86: sysret_rip: Handle syscall in a FRED system Ammar Faizi
2023-01-25 23:01 ` Ammar Faizi
2023-01-25 21:17 ` [RFC PATCH v6 2/3] selftests/x86: sysret_rip: Add more syscall tests with respect to `%rcx` and `%r11` Ammar Faizi
2023-01-25 21:17 ` [RFC PATCH v6 3/3] selftests/x86: sysret_rip: Test opportunistic SYSRET Ammar Faizi
2023-01-25 23:24 ` [RFC PATCH v7 0/3] sysret_rip update for the Intel FRED architecture Ammar Faizi
2023-01-25 23:24 ` [RFC PATCH v7 1/3] selftests/x86: sysret_rip: Handle syscall in a FRED system Ammar Faizi
2023-01-25 23:24 ` [RFC PATCH v7 2/3] selftests/x86: sysret_rip: Add more syscall tests with respect to `%rcx` and `%r11` Ammar Faizi
2023-01-25 23:24 ` [RFC PATCH v7 3/3] selftests/x86: sysret_rip: Test SYSRET with a signal handler Ammar Faizi
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