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linux/arch/loongarch/kernel/entry.S

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LoongArch: Add system call support Add system call support and related uaccess.h for LoongArch. Q: Why keep _ARCH_WANT_SYS_CLONE definition while there is clone3: A: The latest glibc release has some basic support for clone3 but it is not complete. E.g., pthread_create() and spawni() have converted to use clone3 but fork() will still use clone. Moreover, some seccomp related applications can still not work perfectly with clone3. E.g., Chromium sandbox cannot work at all and there is no solution for it, which is more terrible than the fork() story [1]. [1] https://chromium-review.googlesource.com/c/chromium/src/+/2936184 Reviewed-by: WANG Xuerui <git@xen0n.name> Reviewed-by: Jiaxun Yang <jiaxun.yang@flygoat.com> Signed-off-by: Huacai Chen <chenhuacai@loongson.cn>
2022-05-31 10:04:11 +00:00
/* SPDX-License-Identifier: GPL-2.0 */
/*
* Copyright (C) 2020-2022 Loongson Technology Corporation Limited
*
* Derived from MIPS:
* Copyright (C) 1994 - 2000, 2001, 2003 Ralf Baechle
* Copyright (C) 1999, 2000 Silicon Graphics, Inc.
* Copyright (C) 2001 MIPS Technologies, Inc.
*/
#include <asm/asm.h>
#include <asm/asmmacro.h>
#include <asm/loongarch.h>
#include <asm/regdef.h>
#include <asm/stackframe.h>
#include <asm/thread_info.h>
LoongArch: Add ORC stack unwinder support The kernel CONFIG_UNWINDER_ORC option enables the ORC unwinder, which is similar in concept to a DWARF unwinder. The difference is that the format of the ORC data is much simpler than DWARF, which in turn allows the ORC unwinder to be much simpler and faster. The ORC data consists of unwind tables which are generated by objtool. After analyzing all the code paths of a .o file, it determines information about the stack state at each instruction address in the file and outputs that information to the .orc_unwind and .orc_unwind_ip sections. The per-object ORC sections are combined at link time and are sorted and post-processed at boot time. The unwinder uses the resulting data to correlate instruction addresses with their stack states at run time. Most of the logic are similar with x86, in order to get ra info before ra is saved into stack, add ra_reg and ra_offset into orc_entry. At the same time, modify some arch-specific code to silence the objtool warnings. Co-developed-by: Jinyang He <hejinyang@loongson.cn> Signed-off-by: Jinyang He <hejinyang@loongson.cn> Co-developed-by: Youling Tang <tangyouling@loongson.cn> Signed-off-by: Youling Tang <tangyouling@loongson.cn> Signed-off-by: Tiezhu Yang <yangtiezhu@loongson.cn> Signed-off-by: Huacai Chen <chenhuacai@loongson.cn>
2024-03-11 14:23:47 +00:00
#include <asm/unwind_hints.h>
LoongArch: Add system call support Add system call support and related uaccess.h for LoongArch. Q: Why keep _ARCH_WANT_SYS_CLONE definition while there is clone3: A: The latest glibc release has some basic support for clone3 but it is not complete. E.g., pthread_create() and spawni() have converted to use clone3 but fork() will still use clone. Moreover, some seccomp related applications can still not work perfectly with clone3. E.g., Chromium sandbox cannot work at all and there is no solution for it, which is more terrible than the fork() story [1]. [1] https://chromium-review.googlesource.com/c/chromium/src/+/2936184 Reviewed-by: WANG Xuerui <git@xen0n.name> Reviewed-by: Jiaxun Yang <jiaxun.yang@flygoat.com> Signed-off-by: Huacai Chen <chenhuacai@loongson.cn>
2022-05-31 10:04:11 +00:00
.text
.cfi_sections .debug_frame
.align 5
LoongArch: Use SYM_CODE_* to annotate exception handlers As described in include/linux/linkage.h, FUNC -- C-like functions (proper stack frame etc.) CODE -- non-C code (e.g. irq handlers with different, special stack etc.) SYM_FUNC_{START, END} -- use for global functions SYM_CODE_{START, END} -- use for non-C (special) functions So use SYM_CODE_* to annotate exception handlers. Signed-off-by: Tiezhu Yang <yangtiezhu@loongson.cn> Signed-off-by: Huacai Chen <chenhuacai@loongson.cn>
2023-10-18 00:42:52 +00:00
SYM_CODE_START(handle_syscall)
LoongArch: Add ORC stack unwinder support The kernel CONFIG_UNWINDER_ORC option enables the ORC unwinder, which is similar in concept to a DWARF unwinder. The difference is that the format of the ORC data is much simpler than DWARF, which in turn allows the ORC unwinder to be much simpler and faster. The ORC data consists of unwind tables which are generated by objtool. After analyzing all the code paths of a .o file, it determines information about the stack state at each instruction address in the file and outputs that information to the .orc_unwind and .orc_unwind_ip sections. The per-object ORC sections are combined at link time and are sorted and post-processed at boot time. The unwinder uses the resulting data to correlate instruction addresses with their stack states at run time. Most of the logic are similar with x86, in order to get ra info before ra is saved into stack, add ra_reg and ra_offset into orc_entry. At the same time, modify some arch-specific code to silence the objtool warnings. Co-developed-by: Jinyang He <hejinyang@loongson.cn> Signed-off-by: Jinyang He <hejinyang@loongson.cn> Co-developed-by: Youling Tang <tangyouling@loongson.cn> Signed-off-by: Youling Tang <tangyouling@loongson.cn> Signed-off-by: Tiezhu Yang <yangtiezhu@loongson.cn> Signed-off-by: Huacai Chen <chenhuacai@loongson.cn>
2024-03-11 14:23:47 +00:00
UNWIND_HINT_UNDEFINED
LoongArch: Use la.pcrel instead of la.abs when it's trivially possible Let's start to kill la.abs in preparation for the subsequent support of the PIE kernel. BTW, Re-tab the indention in arch/loongarch/kernel/entry.S for alignment. Signed-off-by: Xi Ruoyao <xry111@xry111.site> Signed-off-by: Huacai Chen <chenhuacai@loongson.cn>
2023-02-25 07:52:56 +00:00
csrrd t0, PERCPU_BASE_KS
la.pcrel t1, kernelsp
add.d t1, t1, t0
move t2, sp
ld.d sp, t1, 0
LoongArch: Add system call support Add system call support and related uaccess.h for LoongArch. Q: Why keep _ARCH_WANT_SYS_CLONE definition while there is clone3: A: The latest glibc release has some basic support for clone3 but it is not complete. E.g., pthread_create() and spawni() have converted to use clone3 but fork() will still use clone. Moreover, some seccomp related applications can still not work perfectly with clone3. E.g., Chromium sandbox cannot work at all and there is no solution for it, which is more terrible than the fork() story [1]. [1] https://chromium-review.googlesource.com/c/chromium/src/+/2936184 Reviewed-by: WANG Xuerui <git@xen0n.name> Reviewed-by: Jiaxun Yang <jiaxun.yang@flygoat.com> Signed-off-by: Huacai Chen <chenhuacai@loongson.cn>
2022-05-31 10:04:11 +00:00
LoongArch: Use la.pcrel instead of la.abs when it's trivially possible Let's start to kill la.abs in preparation for the subsequent support of the PIE kernel. BTW, Re-tab the indention in arch/loongarch/kernel/entry.S for alignment. Signed-off-by: Xi Ruoyao <xry111@xry111.site> Signed-off-by: Huacai Chen <chenhuacai@loongson.cn>
2023-02-25 07:52:56 +00:00
addi.d sp, sp, -PT_SIZE
cfi_st t2, PT_R3
LoongArch: Re-tab the assembly files Reflow the *.S files for better stylistic consistency, namely hard tabs after mnemonic position, and vertical alignment of the first operand with hard tabs. Tab width is obviously 8. Some pre-existing intra-block vertical alignments are preserved. Signed-off-by: WANG Xuerui <git@xen0n.name> Signed-off-by: Huacai Chen <chenhuacai@loongson.cn>
2022-07-26 15:57:22 +00:00
cfi_rel_offset sp, PT_R3
LoongArch: Use la.pcrel instead of la.abs when it's trivially possible Let's start to kill la.abs in preparation for the subsequent support of the PIE kernel. BTW, Re-tab the indention in arch/loongarch/kernel/entry.S for alignment. Signed-off-by: Xi Ruoyao <xry111@xry111.site> Signed-off-by: Huacai Chen <chenhuacai@loongson.cn>
2023-02-25 07:52:56 +00:00
st.d zero, sp, PT_R0
csrrd t2, LOONGARCH_CSR_PRMD
st.d t2, sp, PT_PRMD
csrrd t2, LOONGARCH_CSR_CRMD
st.d t2, sp, PT_CRMD
csrrd t2, LOONGARCH_CSR_EUEN
st.d t2, sp, PT_EUEN
csrrd t2, LOONGARCH_CSR_ECFG
st.d t2, sp, PT_ECFG
csrrd t2, LOONGARCH_CSR_ESTAT
st.d t2, sp, PT_ESTAT
cfi_st ra, PT_R1
cfi_st a0, PT_R4
cfi_st a1, PT_R5
cfi_st a2, PT_R6
cfi_st a3, PT_R7
cfi_st a4, PT_R8
cfi_st a5, PT_R9
cfi_st a6, PT_R10
cfi_st a7, PT_R11
csrrd ra, LOONGARCH_CSR_ERA
st.d ra, sp, PT_ERA
LoongArch: Re-tab the assembly files Reflow the *.S files for better stylistic consistency, namely hard tabs after mnemonic position, and vertical alignment of the first operand with hard tabs. Tab width is obviously 8. Some pre-existing intra-block vertical alignments are preserved. Signed-off-by: WANG Xuerui <git@xen0n.name> Signed-off-by: Huacai Chen <chenhuacai@loongson.cn>
2022-07-26 15:57:22 +00:00
cfi_rel_offset ra, PT_ERA
LoongArch: Add system call support Add system call support and related uaccess.h for LoongArch. Q: Why keep _ARCH_WANT_SYS_CLONE definition while there is clone3: A: The latest glibc release has some basic support for clone3 but it is not complete. E.g., pthread_create() and spawni() have converted to use clone3 but fork() will still use clone. Moreover, some seccomp related applications can still not work perfectly with clone3. E.g., Chromium sandbox cannot work at all and there is no solution for it, which is more terrible than the fork() story [1]. [1] https://chromium-review.googlesource.com/c/chromium/src/+/2936184 Reviewed-by: WANG Xuerui <git@xen0n.name> Reviewed-by: Jiaxun Yang <jiaxun.yang@flygoat.com> Signed-off-by: Huacai Chen <chenhuacai@loongson.cn>
2022-05-31 10:04:11 +00:00
LoongArch: Use la.pcrel instead of la.abs when it's trivially possible Let's start to kill la.abs in preparation for the subsequent support of the PIE kernel. BTW, Re-tab the indention in arch/loongarch/kernel/entry.S for alignment. Signed-off-by: Xi Ruoyao <xry111@xry111.site> Signed-off-by: Huacai Chen <chenhuacai@loongson.cn>
2023-02-25 07:52:56 +00:00
cfi_st tp, PT_R2
cfi_st u0, PT_R21
cfi_st fp, PT_R22
LoongArch: Add system call support Add system call support and related uaccess.h for LoongArch. Q: Why keep _ARCH_WANT_SYS_CLONE definition while there is clone3: A: The latest glibc release has some basic support for clone3 but it is not complete. E.g., pthread_create() and spawni() have converted to use clone3 but fork() will still use clone. Moreover, some seccomp related applications can still not work perfectly with clone3. E.g., Chromium sandbox cannot work at all and there is no solution for it, which is more terrible than the fork() story [1]. [1] https://chromium-review.googlesource.com/c/chromium/src/+/2936184 Reviewed-by: WANG Xuerui <git@xen0n.name> Reviewed-by: Jiaxun Yang <jiaxun.yang@flygoat.com> Signed-off-by: Huacai Chen <chenhuacai@loongson.cn>
2022-05-31 10:04:11 +00:00
SAVE_STATIC
LoongArch: Add ORC stack unwinder support The kernel CONFIG_UNWINDER_ORC option enables the ORC unwinder, which is similar in concept to a DWARF unwinder. The difference is that the format of the ORC data is much simpler than DWARF, which in turn allows the ORC unwinder to be much simpler and faster. The ORC data consists of unwind tables which are generated by objtool. After analyzing all the code paths of a .o file, it determines information about the stack state at each instruction address in the file and outputs that information to the .orc_unwind and .orc_unwind_ip sections. The per-object ORC sections are combined at link time and are sorted and post-processed at boot time. The unwinder uses the resulting data to correlate instruction addresses with their stack states at run time. Most of the logic are similar with x86, in order to get ra info before ra is saved into stack, add ra_reg and ra_offset into orc_entry. At the same time, modify some arch-specific code to silence the objtool warnings. Co-developed-by: Jinyang He <hejinyang@loongson.cn> Signed-off-by: Jinyang He <hejinyang@loongson.cn> Co-developed-by: Youling Tang <tangyouling@loongson.cn> Signed-off-by: Youling Tang <tangyouling@loongson.cn> Signed-off-by: Tiezhu Yang <yangtiezhu@loongson.cn> Signed-off-by: Huacai Chen <chenhuacai@loongson.cn>
2024-03-11 14:23:47 +00:00
UNWIND_HINT_REGS
LoongArch: Add system call support Add system call support and related uaccess.h for LoongArch. Q: Why keep _ARCH_WANT_SYS_CLONE definition while there is clone3: A: The latest glibc release has some basic support for clone3 but it is not complete. E.g., pthread_create() and spawni() have converted to use clone3 but fork() will still use clone. Moreover, some seccomp related applications can still not work perfectly with clone3. E.g., Chromium sandbox cannot work at all and there is no solution for it, which is more terrible than the fork() story [1]. [1] https://chromium-review.googlesource.com/c/chromium/src/+/2936184 Reviewed-by: WANG Xuerui <git@xen0n.name> Reviewed-by: Jiaxun Yang <jiaxun.yang@flygoat.com> Signed-off-by: Huacai Chen <chenhuacai@loongson.cn>
2022-05-31 10:04:11 +00:00
LoongArch: Add basic KGDB & KDB support KGDB is intended to be used as a source level debugger for the Linux kernel. It is used along with gdb to debug a Linux kernel. GDB can be used to "break in" to the kernel to inspect memory, variables and regs similar to the way an application developer would use GDB to debug an application. KDB is a frontend of KGDB which is similar to GDB. By now, in addition to the generic KGDB features, the LoongArch KGDB implements the following features: - Hardware breakpoints/watchpoints; - Software single-step support for KDB. Signed-off-by: Qing Zhang <zhangqing@loongson.cn> # Framework & CoreFeature Signed-off-by: Binbin Zhou <zhoubinbin@loongson.cn> # BreakPoint & SingleStep Signed-off-by: Hui Li <lihui@loongson.cn> # Some Minor Improvements Signed-off-by: Randy Dunlap <rdunlap@infradead.org> # Some Build Error Fixes Signed-off-by: Huacai Chen <chenhuacai@loongson.cn>
2023-09-06 14:53:55 +00:00
#ifdef CONFIG_KGDB
li.w t1, CSR_CRMD_WE
csrxchg t1, t1, LOONGARCH_CSR_CRMD
#endif
LoongArch: Use la.pcrel instead of la.abs when it's trivially possible Let's start to kill la.abs in preparation for the subsequent support of the PIE kernel. BTW, Re-tab the indention in arch/loongarch/kernel/entry.S for alignment. Signed-off-by: Xi Ruoyao <xry111@xry111.site> Signed-off-by: Huacai Chen <chenhuacai@loongson.cn>
2023-02-25 07:52:56 +00:00
move u0, t0
li.d tp, ~_THREAD_MASK
and tp, tp, sp
LoongArch: Add system call support Add system call support and related uaccess.h for LoongArch. Q: Why keep _ARCH_WANT_SYS_CLONE definition while there is clone3: A: The latest glibc release has some basic support for clone3 but it is not complete. E.g., pthread_create() and spawni() have converted to use clone3 but fork() will still use clone. Moreover, some seccomp related applications can still not work perfectly with clone3. E.g., Chromium sandbox cannot work at all and there is no solution for it, which is more terrible than the fork() story [1]. [1] https://chromium-review.googlesource.com/c/chromium/src/+/2936184 Reviewed-by: WANG Xuerui <git@xen0n.name> Reviewed-by: Jiaxun Yang <jiaxun.yang@flygoat.com> Signed-off-by: Huacai Chen <chenhuacai@loongson.cn>
2022-05-31 10:04:11 +00:00
LoongArch: Use la.pcrel instead of la.abs when it's trivially possible Let's start to kill la.abs in preparation for the subsequent support of the PIE kernel. BTW, Re-tab the indention in arch/loongarch/kernel/entry.S for alignment. Signed-off-by: Xi Ruoyao <xry111@xry111.site> Signed-off-by: Huacai Chen <chenhuacai@loongson.cn>
2023-02-25 07:52:56 +00:00
move a0, sp
bl do_syscall
LoongArch: Add system call support Add system call support and related uaccess.h for LoongArch. Q: Why keep _ARCH_WANT_SYS_CLONE definition while there is clone3: A: The latest glibc release has some basic support for clone3 but it is not complete. E.g., pthread_create() and spawni() have converted to use clone3 but fork() will still use clone. Moreover, some seccomp related applications can still not work perfectly with clone3. E.g., Chromium sandbox cannot work at all and there is no solution for it, which is more terrible than the fork() story [1]. [1] https://chromium-review.googlesource.com/c/chromium/src/+/2936184 Reviewed-by: WANG Xuerui <git@xen0n.name> Reviewed-by: Jiaxun Yang <jiaxun.yang@flygoat.com> Signed-off-by: Huacai Chen <chenhuacai@loongson.cn>
2022-05-31 10:04:11 +00:00
RESTORE_ALL_AND_RET
LoongArch: Use SYM_CODE_* to annotate exception handlers As described in include/linux/linkage.h, FUNC -- C-like functions (proper stack frame etc.) CODE -- non-C code (e.g. irq handlers with different, special stack etc.) SYM_FUNC_{START, END} -- use for global functions SYM_CODE_{START, END} -- use for non-C (special) functions So use SYM_CODE_* to annotate exception handlers. Signed-off-by: Tiezhu Yang <yangtiezhu@loongson.cn> Signed-off-by: Huacai Chen <chenhuacai@loongson.cn>
2023-10-18 00:42:52 +00:00
SYM_CODE_END(handle_syscall)
LoongArch: Mark some assembler symbols as non-kprobe-able Some assembler symbols are not kprobe safe, such as handle_syscall (used as syscall exception handler), *memset*/*memcpy*/*memmove* (may cause recursive exceptions), they can not be instrumented, just blacklist them for kprobing. Here is a related problem and discussion: Link: https://lore.kernel.org/lkml/20230114143859.7ccc45c1c5d9ce302113ab0a@kernel.org/ Tested-by: Jeff Xie <xiehuan09@gmail.com> Signed-off-by: Tiezhu Yang <yangtiezhu@loongson.cn> Signed-off-by: Huacai Chen <chenhuacai@loongson.cn>
2023-02-25 07:52:57 +00:00
_ASM_NOKPROBE(handle_syscall)
LoongArch: Add system call support Add system call support and related uaccess.h for LoongArch. Q: Why keep _ARCH_WANT_SYS_CLONE definition while there is clone3: A: The latest glibc release has some basic support for clone3 but it is not complete. E.g., pthread_create() and spawni() have converted to use clone3 but fork() will still use clone. Moreover, some seccomp related applications can still not work perfectly with clone3. E.g., Chromium sandbox cannot work at all and there is no solution for it, which is more terrible than the fork() story [1]. [1] https://chromium-review.googlesource.com/c/chromium/src/+/2936184 Reviewed-by: WANG Xuerui <git@xen0n.name> Reviewed-by: Jiaxun Yang <jiaxun.yang@flygoat.com> Signed-off-by: Huacai Chen <chenhuacai@loongson.cn>
2022-05-31 10:04:11 +00:00
SYM_CODE_START(ret_from_fork)
LoongArch: Add ORC stack unwinder support The kernel CONFIG_UNWINDER_ORC option enables the ORC unwinder, which is similar in concept to a DWARF unwinder. The difference is that the format of the ORC data is much simpler than DWARF, which in turn allows the ORC unwinder to be much simpler and faster. The ORC data consists of unwind tables which are generated by objtool. After analyzing all the code paths of a .o file, it determines information about the stack state at each instruction address in the file and outputs that information to the .orc_unwind and .orc_unwind_ip sections. The per-object ORC sections are combined at link time and are sorted and post-processed at boot time. The unwinder uses the resulting data to correlate instruction addresses with their stack states at run time. Most of the logic are similar with x86, in order to get ra info before ra is saved into stack, add ra_reg and ra_offset into orc_entry. At the same time, modify some arch-specific code to silence the objtool warnings. Co-developed-by: Jinyang He <hejinyang@loongson.cn> Signed-off-by: Jinyang He <hejinyang@loongson.cn> Co-developed-by: Youling Tang <tangyouling@loongson.cn> Signed-off-by: Youling Tang <tangyouling@loongson.cn> Signed-off-by: Tiezhu Yang <yangtiezhu@loongson.cn> Signed-off-by: Huacai Chen <chenhuacai@loongson.cn>
2024-03-11 14:23:47 +00:00
UNWIND_HINT_REGS
LoongArch: Use la.pcrel instead of la.abs when it's trivially possible Let's start to kill la.abs in preparation for the subsequent support of the PIE kernel. BTW, Re-tab the indention in arch/loongarch/kernel/entry.S for alignment. Signed-off-by: Xi Ruoyao <xry111@xry111.site> Signed-off-by: Huacai Chen <chenhuacai@loongson.cn>
2023-02-25 07:52:56 +00:00
bl schedule_tail # a0 = struct task_struct *prev
move a0, sp
bl syscall_exit_to_user_mode
LoongArch: Add system call support Add system call support and related uaccess.h for LoongArch. Q: Why keep _ARCH_WANT_SYS_CLONE definition while there is clone3: A: The latest glibc release has some basic support for clone3 but it is not complete. E.g., pthread_create() and spawni() have converted to use clone3 but fork() will still use clone. Moreover, some seccomp related applications can still not work perfectly with clone3. E.g., Chromium sandbox cannot work at all and there is no solution for it, which is more terrible than the fork() story [1]. [1] https://chromium-review.googlesource.com/c/chromium/src/+/2936184 Reviewed-by: WANG Xuerui <git@xen0n.name> Reviewed-by: Jiaxun Yang <jiaxun.yang@flygoat.com> Signed-off-by: Huacai Chen <chenhuacai@loongson.cn>
2022-05-31 10:04:11 +00:00
RESTORE_STATIC
RESTORE_SOME
RESTORE_SP_AND_RET
SYM_CODE_END(ret_from_fork)
SYM_CODE_START(ret_from_kernel_thread)
LoongArch: Add ORC stack unwinder support The kernel CONFIG_UNWINDER_ORC option enables the ORC unwinder, which is similar in concept to a DWARF unwinder. The difference is that the format of the ORC data is much simpler than DWARF, which in turn allows the ORC unwinder to be much simpler and faster. The ORC data consists of unwind tables which are generated by objtool. After analyzing all the code paths of a .o file, it determines information about the stack state at each instruction address in the file and outputs that information to the .orc_unwind and .orc_unwind_ip sections. The per-object ORC sections are combined at link time and are sorted and post-processed at boot time. The unwinder uses the resulting data to correlate instruction addresses with their stack states at run time. Most of the logic are similar with x86, in order to get ra info before ra is saved into stack, add ra_reg and ra_offset into orc_entry. At the same time, modify some arch-specific code to silence the objtool warnings. Co-developed-by: Jinyang He <hejinyang@loongson.cn> Signed-off-by: Jinyang He <hejinyang@loongson.cn> Co-developed-by: Youling Tang <tangyouling@loongson.cn> Signed-off-by: Youling Tang <tangyouling@loongson.cn> Signed-off-by: Tiezhu Yang <yangtiezhu@loongson.cn> Signed-off-by: Huacai Chen <chenhuacai@loongson.cn>
2024-03-11 14:23:47 +00:00
UNWIND_HINT_REGS
LoongArch: Use la.pcrel instead of la.abs when it's trivially possible Let's start to kill la.abs in preparation for the subsequent support of the PIE kernel. BTW, Re-tab the indention in arch/loongarch/kernel/entry.S for alignment. Signed-off-by: Xi Ruoyao <xry111@xry111.site> Signed-off-by: Huacai Chen <chenhuacai@loongson.cn>
2023-02-25 07:52:56 +00:00
bl schedule_tail # a0 = struct task_struct *prev
move a0, s1
jirl ra, s0, 0
move a0, sp
bl syscall_exit_to_user_mode
LoongArch: Add system call support Add system call support and related uaccess.h for LoongArch. Q: Why keep _ARCH_WANT_SYS_CLONE definition while there is clone3: A: The latest glibc release has some basic support for clone3 but it is not complete. E.g., pthread_create() and spawni() have converted to use clone3 but fork() will still use clone. Moreover, some seccomp related applications can still not work perfectly with clone3. E.g., Chromium sandbox cannot work at all and there is no solution for it, which is more terrible than the fork() story [1]. [1] https://chromium-review.googlesource.com/c/chromium/src/+/2936184 Reviewed-by: WANG Xuerui <git@xen0n.name> Reviewed-by: Jiaxun Yang <jiaxun.yang@flygoat.com> Signed-off-by: Huacai Chen <chenhuacai@loongson.cn>
2022-05-31 10:04:11 +00:00
RESTORE_STATIC
RESTORE_SOME
RESTORE_SP_AND_RET
SYM_CODE_END(ret_from_kernel_thread)
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