X-Git-Url: http://git.onelab.eu/?a=blobdiff_plain;f=arch%2Fum%2Fsys-i386%2Fbugs.c;h=41b0ab2fe8300ee6efa200557b8686b5dbfe8d0e;hb=c7b5ebbddf7bcd3651947760f423e3783bbe6573;hp=3905bab88902d5efd4afadeed5c3caada5aec077;hpb=a2c21200f1c81b08cb55e417b68150bba439b646;p=linux-2.6.git diff --git a/arch/um/sys-i386/bugs.c b/arch/um/sys-i386/bugs.c index 3905bab88..41b0ab2fe 100644 --- a/arch/um/sys-i386/bugs.c +++ b/arch/um/sys-i386/bugs.c @@ -4,20 +4,21 @@ */ #include -#include #include #include #include +#include #include "kern_util.h" #include "user.h" #include "sysdep/ptrace.h" #include "task.h" +#include "os.h" #define MAXTOKEN 64 /* Set during early boot */ -int cpu_has_cmov = 1; -int cpu_has_xmm = 0; +int host_has_cmov = 1; +int host_has_xmm = 0; static char token(int fd, char *buf, int len, char stop) { @@ -27,13 +28,15 @@ static char token(int fd, char *buf, int len, char stop) ptr = buf; end = &buf[len]; do { - n = read(fd, ptr, sizeof(*ptr)); + n = os_read_file(fd, ptr, sizeof(*ptr)); c = *ptr++; - if(n == 0) return(0); - else if(n != sizeof(*ptr)){ - printk("Reading /proc/cpuinfo failed, " - "errno = %d\n", errno); - return(-errno); + if(n != sizeof(*ptr)){ + if(n == 0) return(0); + printk("Reading /proc/cpuinfo failed, err = %d\n", -n); + if(n < 0) + return(n); + else + return(-EIO); } } while((c != '\n') && (c != stop) && (ptr < end)); @@ -45,45 +48,79 @@ static char token(int fd, char *buf, int len, char stop) return(c); } -static int check_cpu_feature(char *feature, int *have_it) +static int find_cpuinfo_line(int fd, char *key, char *scratch, int len) { - char buf[MAXTOKEN], c; - int fd, len = sizeof(buf)/sizeof(buf[0]), n; - - printk("Checking for host processor %s support...", feature); - fd = open("/proc/cpuinfo", O_RDONLY); - if(fd < 0){ - printk("Couldn't open /proc/cpuinfo, errno = %d\n", errno); - return(0); - } + int n; + char c; - *have_it = 0; - buf[len - 1] = '\0'; + scratch[len - 1] = '\0'; while(1){ - c = token(fd, buf, len - 1, ':'); - if(c <= 0) goto out; + c = token(fd, scratch, len - 1, ':'); + if(c <= 0) + return(0); else if(c != ':'){ printk("Failed to find ':' in /proc/cpuinfo\n"); - goto out; + return(0); } - if(!strncmp(buf, "flags", strlen("flags"))) break; + if(!strncmp(scratch, key, strlen(key))) + return(1); do { - n = read(fd, &c, sizeof(c)); + n = os_read_file(fd, &c, sizeof(c)); if(n != sizeof(c)){ printk("Failed to find newline in " - "/proc/cpuinfo, n = %d, errno = %d\n", - n, errno); - goto out; + "/proc/cpuinfo, err = %d\n", -n); + return(0); } } while(c != '\n'); } + return(0); +} + +int cpu_feature(char *what, char *buf, int len) +{ + int fd, ret = 0; + + fd = os_open_file("/proc/cpuinfo", of_read(OPENFLAGS()), 0); + if(fd < 0){ + printk("Couldn't open /proc/cpuinfo, err = %d\n", -fd); + return(0); + } + + if(!find_cpuinfo_line(fd, what, buf, len)){ + printk("Couldn't find '%s' line in /proc/cpuinfo\n", what); + goto out_close; + } + + token(fd, buf, len, '\n'); + ret = 1; + + out_close: + os_close_file(fd); + return(ret); +} + +static int check_cpu_flag(char *feature, int *have_it) +{ + char buf[MAXTOKEN], c; + int fd, len = sizeof(buf)/sizeof(buf[0]); + + printk("Checking for host processor %s support...", feature); + fd = os_open_file("/proc/cpuinfo", of_read(OPENFLAGS()), 0); + if(fd < 0){ + printk("Couldn't open /proc/cpuinfo, err = %d\n", -fd); + return(0); + } + + *have_it = 0; + if(!find_cpuinfo_line(fd, "flags", buf, sizeof(buf) / sizeof(buf[0]))) + goto out; c = token(fd, buf, len - 1, ' '); if(c < 0) goto out; else if(c != ' '){ - printk("Failed to find ':' in /proc/cpuinfo\n"); + printk("Failed to find ' ' in /proc/cpuinfo\n"); goto out; } @@ -100,48 +137,76 @@ static int check_cpu_feature(char *feature, int *have_it) out: if(*have_it == 0) printk("No\n"); else if(*have_it == 1) printk("Yes\n"); - close(fd); + os_close_file(fd); return(1); } +#if 0 /* This doesn't work in tt mode, plus it's causing compilation problems + * for some people. + */ +static void disable_lcall(void) +{ + struct modify_ldt_ldt_s ldt; + int err; + + bzero(&ldt, sizeof(ldt)); + ldt.entry_number = 7; + ldt.base_addr = 0; + ldt.limit = 0; + err = modify_ldt(1, &ldt, sizeof(ldt)); + if(err) + printk("Failed to disable lcall7 - errno = %d\n", errno); +} +#endif + +void arch_init_thread(void) +{ +#if 0 + disable_lcall(); +#endif +} + void arch_check_bugs(void) { int have_it; - if(access("/proc/cpuinfo", R_OK)){ + if(os_access("/proc/cpuinfo", OS_ACC_R_OK) < 0){ printk("/proc/cpuinfo not available - skipping CPU capability " "checks\n"); return; } - if(check_cpu_feature("cmov", &have_it)) cpu_has_cmov = have_it; - if(check_cpu_feature("xmm", &have_it)) cpu_has_xmm = have_it; + if(check_cpu_flag("cmov", &have_it)) + host_has_cmov = have_it; + if(check_cpu_flag("xmm", &have_it)) + host_has_xmm = have_it; } int arch_handle_signal(int sig, union uml_pt_regs *regs) { - unsigned long ip; + unsigned char tmp[2]; /* This is testing for a cmov (0x0f 0x4x) instruction causing a * SIGILL in init. */ if((sig != SIGILL) || (TASK_PID(get_current()) != 1)) return(0); - ip = UPT_IP(regs); - if((*((char *) ip) != 0x0f) || ((*((char *) (ip + 1)) & 0xf0) != 0x40)) + if (copy_from_user_proc(tmp, (void *) UPT_IP(regs), 2)) + panic("SIGILL in init, could not read instructions!\n"); + if((tmp[0] != 0x0f) || ((tmp[1] & 0xf0) != 0x40)) return(0); - if(cpu_has_cmov == 0) + if(host_has_cmov == 0) panic("SIGILL caused by cmov, which this processor doesn't " "implement, boot a filesystem compiled for older " "processors"); - else if(cpu_has_cmov == 1) + else if(host_has_cmov == 1) panic("SIGILL caused by cmov, which this processor claims to " "implement"); - else if(cpu_has_cmov == -1) + else if(host_has_cmov == -1) panic("SIGILL caused by cmov, couldn't tell if this processor " "implements it, boot a filesystem compiled for older " "processors"); - else panic("Bad value for cpu_has_cmov (%d)", cpu_has_cmov); + else panic("Bad value for host_has_cmov (%d)", host_has_cmov); return(0); }