Dmitry V. Levin
1763fa5f62
On s390/s390x, syscalls with NR up to 255 can be implemented directly using "svc NR", for NR >= 256 "svc 0" with %r1=NR is used. The latter method is allowed for NR < 256, too. When the syscall number specified directly or indirectly is recognized by the kernel, i.e. it is less than its NR_syscalls value, it is stored in %r2 and is available to arch_get_scno via s390_regset.gprs[2]. For syscall numbers >= NR_syscalls this register is set to 0, but %r1 remains unchanged and could be used by arch_get_scno via s390_regset.gprs[1] to decide what the syscall number is. * linux/s390/get_scno.c (arch_get_scno): If s390_regset.gprs[2] is zero, take syscall number from s390_regset.gprs[1]. * NEWS: Mention this fix. This fixes Debian bug #485979 and Fedora bug #1298294.
9 lines
196 B
C
9 lines
196 B
C
/* Return codes: 1 - ok, 0 - ignore, other - error. */
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static int
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arch_get_scno(struct tcb *tcp)
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{
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tcp->scno = s390_regset.gprs[2] ?
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s390_regset.gprs[2] : s390_regset.gprs[1];
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return 1;
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}
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