| lists.openwall.net | lists / announce owl-users owl-dev john-users john-dev passwdqc-users yescrypt popa3d-users / oss-security kernel-hardening musl sabotage tlsify passwords / crypt-dev xvendor / Bugtraq Full-Disclosure linux-kernel linux-netdev linux-ext4 linux-hardening linux-cve-announce PHC | |
|
Open Source and information security mailing list archives
| ||
|
Message-ID: <tencent_62C4A0442C3453142C0FA002@qq.com>
Date: Fri, 29 Aug 2025 01:18:55 +0800
From: "Wentao Guan" <guanwentao@...ontech.com>
To: "关文涛" <guanwentao@...ontech.com>, "Xi Ruoyao" <xry111@...111.site>, "chenhuacai" <chenhuacai@...nel.org>
Cc: "WANG Xuerui" <kernel@...0n.name>, "linux-kernel" <linux-kernel@...r.kernel.org>, "loongarch" <loongarch@...ts.linux.dev>, "占俊" <zhanjun@...ontech.com>
Subject: Re: [PATCH] Loongarch: entry: fix syscall_get_arguments() VS no-bultin-memcpy
Hello Ruoyao,
The quick test results are very interesting...:
UnixBench syscall on 3A6000 platform:
./Run syscall -i 10 -c 8
kernel source: v6.16
kernel config:
https://github.com/deepin-community/kernel/blob/linux-6.12.y/arch/loongarch/configs/deepin_loongarch_desktop_defconfig
Use this GCC 15[1]:
result:
1. with no patch:
System Call Overhead 15000.0 8893011.8 5928.7
2. with patch [2] to disable -fno-builtin-memcpy -fno-builtin-memmove -fno-builtin-memset:
System Call Overhead 15000.0 8510415.2 5673.6
lower than patch???
3. with my origin patch [3](+4.9%):
System Call Overhead 15000.0 9336022.1 6224.0
BRs
Wentao Guan
[1]: https://mirrors.edge.kernel.org/pub/tools/crosstool/files/bin/x86_64/15.2.0
[2]:
diff --git a/arch/loongarch/Kconfig b/arch/loongarch/Kconfig
index 4b19f9337..53bbcf31c 100644
--- a/arch/loongarch/Kconfig
+++ b/arch/loongarch/Kconfig
@@ -746,6 +746,9 @@ config ARCH_SUSPEND_POSSIBLE
config ARCH_HIBERNATION_POSSIBLE
def_bool y
+config ARCH_MEMORY_LIBCALL_DISABLE
+ def_bool KASAN || GCC_VERSION >= 140000
+
source "kernel/power/Kconfig"
source "drivers/acpi/Kconfig"
source "drivers/cpufreq/Kconfig"
diff --git a/arch/loongarch/Makefile b/arch/loongarch/Makefile
index b0703a4e0..fba837b22 100644
--- a/arch/loongarch/Makefile
+++ b/arch/loongarch/Makefile
@@ -120,7 +120,7 @@ endif
cflags-y += $(call cc-option, -mno-check-zero-division)
-ifndef CONFIG_KASAN
+ifeq ($(CONFIG_ARCH_MEMORY_LIBCALL_DISABLE),)
cflags-y += -fno-builtin-memcpy -fno-builtin-memmove -fno-builtin-memset
endif
[3]:
diff --git a/arch/loongarch/include/asm/syscall.h b/arch/loongarch/include/asm/syscall.h
index 81d2733f7..171af2edd 100644
--- a/arch/loongarch/include/asm/syscall.h
+++ b/arch/loongarch/include/asm/syscall.h
@@ -65,7 +65,11 @@ static inline void syscall_get_arguments(struct task_struct *task,
unsigned long *args)
{
args[0] = regs->orig_a0;
- memcpy(&args[1], ®s->regs[5], 5 * sizeof(long));
+ args[1] = regs->regs[5];
+ args[2] = regs->regs[6];
+ args[3] = regs->regs[7];
+ args[4] = regs->regs[8];
+ args[5] = regs->regs[9];
}
static inline void syscall_set_arguments(struct task_struct *task,
[4]: perf diff
# Event 'cycles:P'
#
# Baseline Delta Abs Shared Object Symbol >
# ........ ......... .................................. .....................................................>
#
12.72% -7.07% [kernel.kallsyms] [k] syscall_trace_enter
0.00% +2.94% [kernel.kallsyms] [k] __memcpy_fast
33.69% +1.41% [kernel.kallsyms] [k] do_syscall
2.64% +0.32% [kernel.kallsyms] [k] __audit_syscall_entry
4.92% +0.32% libc.so.6 [.] __GI___umask
3.54% +0.30% [kernel.kallsyms] [k] alloc_fd
4.36% +0.24% libc.so.6 [.] __GI___getuid
4.63% +0.24% libc.so.6 [.] syscall
4.50% +0.22% libc.so.6 [.] __GI___dup
4.84% +0.22% [kernel.kallsyms] [k] syscall_exit_work
4.81% +0.22% libc.so.6 [.] __close
+0.20% [kernel.kallsyms] [k] __memcpy
1.48% +0.15% [kernel.kallsyms] [k] audit_reset_context
0.69% +0.13% [kernel.kallsyms] [k] __se_sys_close
2.13% +0.10% [kernel.kallsyms] [k] file_close_fd_locked
0.86% +0.08% [kernel.kallsyms] [k] map_id_range_up
0.71% +0.06% [kernel.kallsyms] [k] __task_pid_nr_ns
0.41% +0.04% [kernel.kallsyms] [k] fd_install
0.56% +0.04% [kernel.kallsyms] [k] __rcu_read_unlock
0.57% +0.04% [kernel.kallsyms] [k] fput_close_sync
0.07% -0.04% [kernel.kallsyms] [k] idle_exit
1.37% +0.04% [kernel.kallsyms] [k] _raw_spin_lock
0.69% +0.03% [kernel.kallsyms] [k] filp_flush
0.76% +0.03% syscall [.] main
0.52% +0.03% [kernel.kallsyms] [k] from_kuid_munged
0.45% +0.03% [kernel.kallsyms] [k] _raw_spin_unlock
0.07% -0.03% [kernel.kallsyms] [k] finish_task_switch.isra.0
1.72% +0.03% [kernel.kallsyms] [k] ktime_get_coarse_real_ts64
0.67% +0.03% [kernel.kallsyms] [k] __rcu_read_lock
0.03% -0.03% deepin-deepinid-daemon [.] 0x0000000000003018
1.28% -0.02% [kernel.kallsyms] [k] __audit_syscall_exit
0.12% +0.02% syscall [.] getuid@plt
0.02% -0.02% dde-session-daemon [.] 0x0000000000299d10
0.02% -0.02% ld-linux-loongarch-lp64d.so.1 [.] do_lookup_x
0.03% -0.01% [kernel.kallsyms] [k] _raw_spin_unlock_irqrestore
0.01% -0.01% ld-linux-loongarch-lp64d.so.1 [.] _dl_lookup_symbol_x
0.30% +0.01% [kernel.kallsyms] [k] sys_getpid
0.14% -0.01% syscall [.] umask@plt
0.01% -0.01% libdbus-1.so.3.32.4 [.] 0x0000000000015ac0
0.02% -0.01% [kernel.kallsyms] [k] clear_page
0.01% -0.01% deepin-sync-helper [.] 0x0000000000003a84
0.14% +0.01% syscall [.] close@plt
Powered by blists - more mailing lists