From 1fb9bdaf59719c0d0c28043e58c8e3452fd6d7de Mon Sep 17 00:00:00 2001 From: Ilya Leoshkevich Date: Mon, 5 Jun 2023 13:39:50 +0200 Subject: [PATCH] linux-user: Emulate /proc/cpuinfo on s390x Some s390x userspace programs are confused when seeing a foreign /proc/cpuinfo [1]. Add the emulation for s390x; follow the respective kernel code structure where possible. Output example: vendor_id : IBM/S390 # processors : 12 bogomips per cpu: 13370.00 max thread id : 0 features : esan3 zarch stfle msa facilities : 0 1 2 3 4 7 9 16 17 18 19 21 22 24 25 27 30 31 32 33 34 35 37 40 41 45 49 51 52 53 57 58 61 69 71 72 75 76 77 129 130 131 135 138 146 148 processor 0: version = 00, identification = 000000, machine = 8561 processor 1: version = 00, identification = 100000, machine = 8561 [...] cpu number : 0 version : 00 identification : 000000 machine : 8561 cpu number : 1 version : 00 identification : 100000 machine : 8561 [...] [1] https://bugzilla.redhat.com/show_bug.cgi?id=2211472 Reported-by: Tulio Magno Quites Machado Filho Reviewed-by: David Hildenbrand Signed-off-by: Ilya Leoshkevich Message-Id: <20230605113950.1169228-5-iii@linux.ibm.com> Signed-off-by: Thomas Huth --- linux-user/syscall.c | 106 ++++++++++++++++++++++++++++++++++++++++++- 1 file changed, 104 insertions(+), 2 deletions(-) diff --git a/linux-user/syscall.c b/linux-user/syscall.c index 89b58b386b..83685f0aa5 100644 --- a/linux-user/syscall.c +++ b/linux-user/syscall.c @@ -8232,7 +8232,7 @@ void target_exception_dump(CPUArchState *env, const char *fmt, int code) #if HOST_BIG_ENDIAN != TARGET_BIG_ENDIAN || \ defined(TARGET_SPARC) || defined(TARGET_M68K) || defined(TARGET_HPPA) || \ - defined(TARGET_RISCV) + defined(TARGET_RISCV) || defined(TARGET_S390X) static int is_proc(const char *filename, const char *entry) { return strcmp(filename, entry) == 0; @@ -8339,6 +8339,107 @@ static int open_cpuinfo(CPUArchState *cpu_env, int fd) } #endif +#if defined(TARGET_S390X) +/* + * Emulate what a Linux kernel running in qemu-system-s390x -M accel=tcg would + * show in /proc/cpuinfo. + * + * Skip the following in order to match the missing support in op_ecag(): + * - show_cacheinfo(). + * - show_cpu_topology(). + * - show_cpu_mhz(). + * + * Use fixed values for certain fields: + * - bogomips per cpu - from a qemu-system-s390x run. + * - max thread id = 0, since SMT / SIGP_SET_MULTI_THREADING is not supported. + * + * Keep the code structure close to arch/s390/kernel/processor.c. + */ + +static void show_facilities(int fd) +{ + size_t sizeof_stfl_bytes = 2048; + g_autofree uint8_t *stfl_bytes = g_new0(uint8_t, sizeof_stfl_bytes); + unsigned int bit; + + dprintf(fd, "facilities :"); + s390_get_feat_block(S390_FEAT_TYPE_STFL, stfl_bytes); + for (bit = 0; bit < sizeof_stfl_bytes * 8; bit++) { + if (test_be_bit(bit, stfl_bytes)) { + dprintf(fd, " %d", bit); + } + } + dprintf(fd, "\n"); +} + +static int cpu_ident(unsigned long n) +{ + return deposit32(0, CPU_ID_BITS - CPU_PHYS_ADDR_BITS, CPU_PHYS_ADDR_BITS, + n); +} + +static void show_cpu_summary(CPUArchState *cpu_env, int fd) +{ + S390CPUModel *model = env_archcpu(cpu_env)->model; + int num_cpus = sysconf(_SC_NPROCESSORS_ONLN); + uint32_t elf_hwcap = get_elf_hwcap(); + const char *hwcap_str; + int i; + + dprintf(fd, "vendor_id : IBM/S390\n" + "# processors : %i\n" + "bogomips per cpu: 13370.00\n", + num_cpus); + dprintf(fd, "max thread id : 0\n"); + dprintf(fd, "features\t: "); + for (i = 0; i < sizeof(elf_hwcap) * 8; i++) { + if (!(elf_hwcap & (1 << i))) { + continue; + } + hwcap_str = elf_hwcap_str(i); + if (hwcap_str) { + dprintf(fd, "%s ", hwcap_str); + } + } + dprintf(fd, "\n"); + show_facilities(fd); + for (i = 0; i < num_cpus; i++) { + dprintf(fd, "processor %d: " + "version = %02X, " + "identification = %06X, " + "machine = %04X\n", + i, model->cpu_ver, cpu_ident(i), model->def->type); + } +} + +static void show_cpu_ids(CPUArchState *cpu_env, int fd, unsigned long n) +{ + S390CPUModel *model = env_archcpu(cpu_env)->model; + + dprintf(fd, "version : %02X\n", model->cpu_ver); + dprintf(fd, "identification : %06X\n", cpu_ident(n)); + dprintf(fd, "machine : %04X\n", model->def->type); +} + +static void show_cpuinfo(CPUArchState *cpu_env, int fd, unsigned long n) +{ + dprintf(fd, "\ncpu number : %ld\n", n); + show_cpu_ids(cpu_env, fd, n); +} + +static int open_cpuinfo(CPUArchState *cpu_env, int fd) +{ + int num_cpus = sysconf(_SC_NPROCESSORS_ONLN); + int i; + + show_cpu_summary(cpu_env, fd); + for (i = 0; i < num_cpus; i++) { + show_cpuinfo(cpu_env, fd, i); + } + return 0; +} +#endif + #if defined(TARGET_M68K) static int open_hardware(CPUArchState *cpu_env, int fd) { @@ -8363,7 +8464,8 @@ static int do_openat(CPUArchState *cpu_env, int dirfd, const char *pathname, int #if HOST_BIG_ENDIAN != TARGET_BIG_ENDIAN { "/proc/net/route", open_net_route, is_proc }, #endif -#if defined(TARGET_SPARC) || defined(TARGET_HPPA) || defined(TARGET_RISCV) +#if defined(TARGET_SPARC) || defined(TARGET_HPPA) || \ + defined(TARGET_RISCV) || defined(TARGET_S390X) { "/proc/cpuinfo", open_cpuinfo, is_proc }, #endif #if defined(TARGET_M68K)