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From: Pedro Falcato <pedro.falcato@gmail.com>
To: musl@lists.openwall.com
Cc: Pedro Falcato <pedro.falcato@gmail.com>
Subject: [musl] [PATCH v2] riscv64: Add vfork
Date: Thu,  9 Feb 2023 16:34:12 +0000	[thread overview]
Message-ID: <20230209163412.266391-1-pedro.falcato@gmail.com> (raw)

Implement vfork() using clone(CLONE_VM | CLONE_VFORK | ...).
---
 src/process/riscv64/vfork.s | 12 ++++++++++++
 1 file changed, 12 insertions(+)
 create mode 100644 src/process/riscv64/vfork.s

diff --git a/src/process/riscv64/vfork.s b/src/process/riscv64/vfork.s
new file mode 100644
index 00000000..c93dca23
--- /dev/null
+++ b/src/process/riscv64/vfork.s
@@ -0,0 +1,12 @@
+.global vfork
+.type vfork,@function
+vfork:
+	/* riscv does not have SYS_vfork, so we must use clone instead */
+	/* note: riscv's clone = clone(flags, sp, ptidptr, tls, ctidptr) */
+	li a7, 220
+	li a0, 0x100 | 0x4000 | 17 /* flags = CLONE_VM | CLONE_VFORK | SIGCHLD */
+	mv a1, sp
+	/* the other arguments are ignoreable */
+	ecall
+	.hidden __syscall_ret
+	j __syscall_ret
-- 
2.39.1


                 reply	other threads:[~2023-02-09 16:34 UTC|newest]

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