From: Lai Jiangshan <jiangshanlai@gmail.com>
To: linux-kernel@vger.kernel.org
Cc: Borislav Petkov <bp@alien8.de>,
Peter Zijlstra <peterz@infradead.org>,
Josh Poimboeuf <jpoimboe@redhat.com>,
Andy Lutomirski <luto@kernel.org>,
Thomas Gleixner <tglx@linutronix.de>,
x86@kernel.org, Lai Jiangshan <jiangshan.ljs@antgroup.com>,
Ingo Molnar <mingo@redhat.com>,
Dave Hansen <dave.hansen@linux.intel.com>,
"H. Peter Anvin" <hpa@zytor.com>
Subject: [PATCH V2 4/7] x86/entry: Add arch/x86/entry/entry64.c for C entry code
Date: Mon, 16 May 2022 21:17:35 +0800 [thread overview]
Message-ID: <20220516131739.521817-5-jiangshanlai@gmail.com> (raw)
In-Reply-To: <20220516131739.521817-1-jiangshanlai@gmail.com>
From: Lai Jiangshan <jiangshan.ljs@antgroup.com>
Add a C file "entry64.c" to deposit C entry code for traps and faults
which will be as the same logic as the existing ASM code in entry_64.S.
The file is as low level as entry_64.S and its code can be running in
the environments that the GS base is a user controlled value, or
the CR3 is the KPTI user CR3 or both.
All the code in this file should not be instrumentable. Many instrument
facilities can be disabled by per-function attributes which are included
in the macro __noinstr_section. But stack-protector can not be disabled
function-granularly by some compliers. So stack-protector is disabled
for the whole file in Makefile.
Suggested-by: Joerg Roedel <jroedel@suse.de>
Signed-off-by: Lai Jiangshan <jiangshan.ljs@antgroup.com>
---
arch/x86/entry/Makefile | 3 ++-
arch/x86/entry/entry64.c | 14 ++++++++++++++
2 files changed, 16 insertions(+), 1 deletion(-)
create mode 100644 arch/x86/entry/entry64.c
diff --git a/arch/x86/entry/Makefile b/arch/x86/entry/Makefile
index 7fec5dcf6438..792f7009ff32 100644
--- a/arch/x86/entry/Makefile
+++ b/arch/x86/entry/Makefile
@@ -10,13 +10,14 @@ KCOV_INSTRUMENT := n
CFLAGS_REMOVE_common.o = $(CC_FLAGS_FTRACE)
CFLAGS_common.o += -fno-stack-protector
+CFLAGS_entry64.o += -fno-stack-protector
obj-y := entry_$(BITS).o thunk_$(BITS).o syscall_$(BITS).o
obj-y += common.o
+obj-$(CONFIG_X86_64) += entry64.o
obj-y += vdso/
obj-y += vsyscall/
obj-$(CONFIG_IA32_EMULATION) += entry_64_compat.o syscall_32.o
obj-$(CONFIG_X86_X32_ABI) += syscall_x32.o
-
diff --git a/arch/x86/entry/entry64.c b/arch/x86/entry/entry64.c
new file mode 100644
index 000000000000..ace73861c2a0
--- /dev/null
+++ b/arch/x86/entry/entry64.c
@@ -0,0 +1,14 @@
+// SPDX-License-Identifier: GPL-2.0-only
+/*
+ * Copyright (C) 1991, 1992 Linus Torvalds
+ * Copyright (C) 2000, 2001, 2002 Andi Kleen SuSE Labs
+ * Copyright (C) 2000 Pavel Machek <pavel@suse.cz>
+ * Copyright (C) 2022 Lai Jiangshan, Ant Group
+ *
+ * Handle entries and exits for hardware traps and faults.
+ *
+ * It is as low level as entry_64.S and its code can be running in the
+ * environments that the GS base is a user controlled value, or the CR3
+ * is the PTI user CR3 or both.
+ */
+#include <asm/traps.h>
--
2.19.1.6.gb485710b
next prev parent reply other threads:[~2022-05-16 13:17 UTC|newest]
Thread overview: 8+ messages / expand[flat|nested] mbox.gz Atom feed top
2022-05-16 13:17 [PATCH V2 0/7] x86/entry: Convert error_entry() to C code Lai Jiangshan
2022-05-16 13:17 ` [PATCH V2 1/7] x86/entry: Introduce __entry_text for entry code written in C Lai Jiangshan
2022-05-16 13:17 ` [PATCH V2 2/7] x86/entry: Move PTI_USER_* to arch/x86/include/asm/processor-flags.h Lai Jiangshan
2022-05-16 13:17 ` [PATCH V2 3/7] x86: Mark __native_read_cr3() & native_write_cr3() as __always_inline Lai Jiangshan
2022-05-16 13:17 ` Lai Jiangshan [this message]
2022-05-16 13:17 ` [PATCH V2 5/7] x86/entry: Add the C verion of SWITCH_TO_KERNEL_CR3 as switch_to_kernel_cr3() Lai Jiangshan
2022-05-16 13:17 ` [PATCH V2 6/7] x86/traps: Add fence_swapgs_{user,kernel}_entry() and user_entry_swapgs_and_fence() Lai Jiangshan
2022-05-16 13:17 ` [PATCH V2 7/7] x86/entry: Implement the whole error_entry() as C code Lai Jiangshan
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=20220516131739.521817-5-jiangshanlai@gmail.com \
--to=jiangshanlai@gmail.com \
--cc=bp@alien8.de \
--cc=dave.hansen@linux.intel.com \
--cc=hpa@zytor.com \
--cc=jiangshan.ljs@antgroup.com \
--cc=jpoimboe@redhat.com \
--cc=linux-kernel@vger.kernel.org \
--cc=luto@kernel.org \
--cc=mingo@redhat.com \
--cc=peterz@infradead.org \
--cc=tglx@linutronix.de \
--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: link
Be sure your reply has a Subject: header at the top and a blank line
before the message body.
This is a public inbox, see mirroring instructions
for how to clone and mirror all data and code used for this inbox;
as well as URLs for NNTP newsgroup(s).