From d1e23cbaa403b2d816e1cb2acd61105d00c38b9b Mon Sep 17 00:00:00 2001 From: Richard Henderson Date: Fri, 29 Apr 2022 18:28:35 -0700 Subject: [PATCH 01/11] target/nios2: Use semihosting/syscalls.h This separates guest file descriptors from host file descriptors, and utilizes shared infrastructure for integration with gdbstub. Signed-off-by: Richard Henderson --- target/nios2/nios2-semi.c | 296 +++++++------------------------------- 1 file changed, 50 insertions(+), 246 deletions(-) diff --git a/target/nios2/nios2-semi.c b/target/nios2/nios2-semi.c index 55061bb2dc..614fd76695 100644 --- a/target/nios2/nios2-semi.c +++ b/target/nios2/nios2-semi.c @@ -24,6 +24,7 @@ #include "qemu/osdep.h" #include "cpu.h" #include "exec/gdbstub.h" +#include "semihosting/syscalls.h" #include "semihosting/softmmu-uaccess.h" #include "qemu/log.h" @@ -42,67 +43,6 @@ #define HOSTED_ISATTY 12 #define HOSTED_SYSTEM 13 -static int translate_openflags(int flags) -{ - int hf; - - if (flags & GDB_O_WRONLY) { - hf = O_WRONLY; - } else if (flags & GDB_O_RDWR) { - hf = O_RDWR; - } else { - hf = O_RDONLY; - } - - if (flags & GDB_O_APPEND) { - hf |= O_APPEND; - } - if (flags & GDB_O_CREAT) { - hf |= O_CREAT; - } - if (flags & GDB_O_TRUNC) { - hf |= O_TRUNC; - } - if (flags & GDB_O_EXCL) { - hf |= O_EXCL; - } - - return hf; -} - -static bool translate_stat(CPUNios2State *env, target_ulong addr, - struct stat *s) -{ - struct gdb_stat *p; - - p = lock_user(VERIFY_WRITE, addr, sizeof(struct gdb_stat), 0); - - if (!p) { - return false; - } - p->gdb_st_dev = cpu_to_be32(s->st_dev); - p->gdb_st_ino = cpu_to_be32(s->st_ino); - p->gdb_st_mode = cpu_to_be32(s->st_mode); - p->gdb_st_nlink = cpu_to_be32(s->st_nlink); - p->gdb_st_uid = cpu_to_be32(s->st_uid); - p->gdb_st_gid = cpu_to_be32(s->st_gid); - p->gdb_st_rdev = cpu_to_be32(s->st_rdev); - p->gdb_st_size = cpu_to_be64(s->st_size); -#ifdef _WIN32 - /* Windows stat is missing some fields. */ - p->gdb_st_blksize = 0; - p->gdb_st_blocks = 0; -#else - p->gdb_st_blksize = cpu_to_be64(s->st_blksize); - p->gdb_st_blocks = cpu_to_be64(s->st_blocks); -#endif - p->gdb_st_atime = cpu_to_be32(s->st_atime); - p->gdb_st_mtime = cpu_to_be32(s->st_mtime); - p->gdb_st_ctime = cpu_to_be32(s->st_ctime); - unlock_user(p, addr, sizeof(struct gdb_stat)); - return true; -} - static void nios2_semi_u32_cb(CPUState *cs, uint64_t ret, int err) { Nios2CPU *cpu = NIOS2_CPU(cs); @@ -142,22 +82,22 @@ static void nios2_semi_u64_cb(CPUState *cs, uint64_t ret, int err) */ #define GET_ARG(n) do { \ if (get_user_ual(arg ## n, args + (n) * 4)) { \ - result = -1; \ - errno = EFAULT; \ goto failed; \ } \ } while (0) +#define GET_ARG64(n) do { \ + if (get_user_ual(arg ## n, args + (n) * 4)) { \ + goto failed64; \ + } \ +} while (0) + void do_nios2_semihosting(CPUNios2State *env) { CPUState *cs = env_cpu(env); int nr; uint32_t args; target_ulong arg0, arg1, arg2, arg3; - void *p; - void *q; - uint32_t len; - uint32_t result; nr = env->regs[R_ARG0]; args = env->regs[R_ARG1]; @@ -165,234 +105,98 @@ void do_nios2_semihosting(CPUNios2State *env) case HOSTED_EXIT: gdb_exit(env->regs[R_ARG0]); exit(env->regs[R_ARG0]); + case HOSTED_OPEN: GET_ARG(0); GET_ARG(1); GET_ARG(2); GET_ARG(3); - if (use_gdb_syscalls()) { - gdb_do_syscall(nios2_semi_u32_cb, "open,%s,%x,%x", arg0, (int)arg1, - arg2, arg3); - return; - } else { - p = lock_user_string(arg0); - if (!p) { - result = -1; - errno = EFAULT; - } else { - result = open(p, translate_openflags(arg2), arg3); - unlock_user(p, arg0, 0); - } - } + semihost_sys_open(cs, nios2_semi_u32_cb, arg0, arg1, arg2, arg3); break; + case HOSTED_CLOSE: - { - /* Ignore attempts to close stdin/out/err. */ - GET_ARG(0); - int fd = arg0; - if (fd > 2) { - if (use_gdb_syscalls()) { - gdb_do_syscall(nios2_semi_u32_cb, "close,%x", arg0); - return; - } else { - result = close(fd); - } - } else { - result = 0; - } - break; - } + GET_ARG(0); + semihost_sys_close(cs, nios2_semi_u32_cb, arg0); + break; + case HOSTED_READ: GET_ARG(0); GET_ARG(1); GET_ARG(2); - len = arg2; - if (use_gdb_syscalls()) { - gdb_do_syscall(nios2_semi_u32_cb, "read,%x,%x,%x", - arg0, arg1, len); - return; - } else { - p = lock_user(VERIFY_WRITE, arg1, len, 0); - if (!p) { - result = -1; - errno = EFAULT; - } else { - result = read(arg0, p, len); - unlock_user(p, arg1, len); - } - } + semihost_sys_read(cs, nios2_semi_u32_cb, arg0, arg1, arg2); break; + case HOSTED_WRITE: GET_ARG(0); GET_ARG(1); GET_ARG(2); - len = arg2; - if (use_gdb_syscalls()) { - gdb_do_syscall(nios2_semi_u32_cb, "write,%x,%x,%x", - arg0, arg1, len); - return; - } else { - p = lock_user(VERIFY_READ, arg1, len, 1); - if (!p) { - result = -1; - errno = EFAULT; - } else { - result = write(arg0, p, len); - unlock_user(p, arg0, 0); - } - } + semihost_sys_write(cs, nios2_semi_u32_cb, arg0, arg1, arg2); break; + case HOSTED_LSEEK: - { - uint64_t off; - GET_ARG(0); - GET_ARG(1); - GET_ARG(2); - GET_ARG(3); - off = (uint32_t)arg2 | ((uint64_t)arg1 << 32); - if (use_gdb_syscalls()) { - gdb_do_syscall(nios2_semi_u64_cb, "lseek,%x,%lx,%x", - arg0, off, arg3); - } else { - off = lseek(arg0, off, arg3); - nios2_semi_u64_cb(cs, off, errno); - } - return; - } + GET_ARG64(0); + GET_ARG64(1); + GET_ARG64(2); + GET_ARG64(3); + semihost_sys_lseek(cs, nios2_semi_u64_cb, arg0, + deposit64(arg2, arg1, 32, 32), arg3); + break; + case HOSTED_RENAME: GET_ARG(0); GET_ARG(1); GET_ARG(2); GET_ARG(3); - if (use_gdb_syscalls()) { - gdb_do_syscall(nios2_semi_u32_cb, "rename,%s,%s", - arg0, (int)arg1, arg2, (int)arg3); - return; - } else { - p = lock_user_string(arg0); - q = lock_user_string(arg2); - if (!p || !q) { - result = -1; - errno = EFAULT; - } else { - result = rename(p, q); - } - unlock_user(p, arg0, 0); - unlock_user(q, arg2, 0); - } + semihost_sys_rename(cs, nios2_semi_u32_cb, arg0, arg1, arg2, arg3); break; + case HOSTED_UNLINK: GET_ARG(0); GET_ARG(1); - if (use_gdb_syscalls()) { - gdb_do_syscall(nios2_semi_u32_cb, "unlink,%s", - arg0, (int)arg1); - return; - } else { - p = lock_user_string(arg0); - if (!p) { - result = -1; - errno = EFAULT; - } else { - result = unlink(p); - unlock_user(p, arg0, 0); - } - } + semihost_sys_remove(cs, nios2_semi_u32_cb, arg0, arg1); break; + case HOSTED_STAT: GET_ARG(0); GET_ARG(1); GET_ARG(2); - if (use_gdb_syscalls()) { - gdb_do_syscall(nios2_semi_u32_cb, "stat,%s,%x", - arg0, (int)arg1, arg2); - return; - } else { - struct stat s; - p = lock_user_string(arg0); - if (!p) { - result = -1; - errno = EFAULT; - } else { - result = stat(p, &s); - unlock_user(p, arg0, 0); - } - if (result == 0 && !translate_stat(env, arg2, &s)) { - result = -1; - errno = EFAULT; - } - } + semihost_sys_stat(cs, nios2_semi_u32_cb, arg0, arg1, arg2); break; + case HOSTED_FSTAT: GET_ARG(0); GET_ARG(1); - if (use_gdb_syscalls()) { - gdb_do_syscall(nios2_semi_u32_cb, "fstat,%x,%x", - arg0, arg1); - return; - } else { - struct stat s; - result = fstat(arg0, &s); - if (result == 0 && !translate_stat(env, arg1, &s)) { - result = -1; - errno = EFAULT; - } - } + semihost_sys_fstat(cs, nios2_semi_u32_cb, arg0, arg1); break; + case HOSTED_GETTIMEOFDAY: - /* Only the tv parameter is used. tz is assumed NULL. */ GET_ARG(0); - if (use_gdb_syscalls()) { - gdb_do_syscall(nios2_semi_u32_cb, "gettimeofday,%x,%x", - arg0, 0); - return; - } else { - struct gdb_timeval *p; - int64_t rt = g_get_real_time(); - p = lock_user(VERIFY_WRITE, arg0, sizeof(struct gdb_timeval), 0); - if (!p) { - result = -1; - errno = EFAULT; - } else { - result = 0; - p->tv_sec = cpu_to_be32(rt / G_USEC_PER_SEC); - p->tv_usec = cpu_to_be64(rt % G_USEC_PER_SEC); - unlock_user(p, arg0, sizeof(struct gdb_timeval)); - } - } + GET_ARG(1); + semihost_sys_gettimeofday(cs, nios2_semi_u32_cb, arg0, arg1); break; + case HOSTED_ISATTY: GET_ARG(0); - if (use_gdb_syscalls()) { - gdb_do_syscall(nios2_semi_u32_cb, "isatty,%x", arg0); - return; - } else { - result = isatty(arg0); - } + semihost_sys_isatty(cs, nios2_semi_u32_cb, arg0); break; + case HOSTED_SYSTEM: GET_ARG(0); GET_ARG(1); - if (use_gdb_syscalls()) { - gdb_do_syscall(nios2_semi_u32_cb, "system,%s", - arg0, (int)arg1); - return; - } else { - p = lock_user_string(arg0); - if (!p) { - result = -1; - errno = EFAULT; - } else { - result = system(p); - unlock_user(p, arg0, 0); - } - } + semihost_sys_system(cs, nios2_semi_u32_cb, arg0, arg1); break; + default: qemu_log_mask(LOG_GUEST_ERROR, "nios2-semihosting: unsupported " "semihosting syscall %d\n", nr); - result = 0; + nios2_semi_u32_cb(cs, -1, ENOSYS); + break; + + failed: + nios2_semi_u32_cb(cs, -1, EFAULT); + break; + failed64: + nios2_semi_u64_cb(cs, -1, EFAULT); + break; } -failed: - nios2_semi_u32_cb(cs, result, errno); } From 78c2c68ddac7b1a73615d89363fffd8c01561123 Mon Sep 17 00:00:00 2001 From: Richard Henderson Date: Mon, 20 Jun 2022 15:19:46 -0700 Subject: [PATCH 02/11] target/nios2: Convert semihosting errno to gdb remote errno The semihosting abi used by nios2 uses the gdb remote protocol filesys errnos. Signed-off-by: Richard Henderson --- target/nios2/nios2-semi.c | 33 +++++++++++++++++++++++++++++++-- 1 file changed, 31 insertions(+), 2 deletions(-) diff --git a/target/nios2/nios2-semi.c b/target/nios2/nios2-semi.c index 614fd76695..f76e8588c5 100644 --- a/target/nios2/nios2-semi.c +++ b/target/nios2/nios2-semi.c @@ -43,6 +43,35 @@ #define HOSTED_ISATTY 12 #define HOSTED_SYSTEM 13 +static int host_to_gdb_errno(int err) +{ +#define E(X) case E##X: return GDB_E##X + switch (err) { + E(PERM); + E(NOENT); + E(INTR); + E(BADF); + E(ACCES); + E(FAULT); + E(BUSY); + E(EXIST); + E(NODEV); + E(NOTDIR); + E(ISDIR); + E(INVAL); + E(NFILE); + E(MFILE); + E(FBIG); + E(NOSPC); + E(SPIPE); + E(ROFS); + E(NAMETOOLONG); + default: + return GDB_EUNKNOWN; + } +#undef E +} + static void nios2_semi_u32_cb(CPUState *cs, uint64_t ret, int err) { Nios2CPU *cpu = NIOS2_CPU(cs); @@ -50,7 +79,7 @@ static void nios2_semi_u32_cb(CPUState *cs, uint64_t ret, int err) target_ulong args = env->regs[R_ARG1]; if (put_user_u32(ret, args) || - put_user_u32(err, args + 4)) { + put_user_u32(host_to_gdb_errno(err), args + 4)) { /* * The nios2 semihosting ABI does not provide any way to report this * error to the guest, so the best we can do is log it in qemu. @@ -69,7 +98,7 @@ static void nios2_semi_u64_cb(CPUState *cs, uint64_t ret, int err) if (put_user_u32(ret >> 32, args) || put_user_u32(ret, args + 4) || - put_user_u32(err, args + 8)) { + put_user_u32(host_to_gdb_errno(err), args + 8)) { /* No way to report this via nios2 semihosting ABI; just log it */ qemu_log_mask(LOG_GUEST_ERROR, "nios2-semihosting: return value " "discarded because argument block not writable\n"); From 950272506dbd8dcf8c74b63e9949d18397e6a0ec Mon Sep 17 00:00:00 2001 From: Richard Henderson Date: Fri, 29 Apr 2022 17:38:59 -0700 Subject: [PATCH 03/11] target/m68k: Use semihosting/syscalls.h This separates guest file descriptors from host file descriptors, and utilizes shared infrastructure for integration with gdbstub. Acked-by: Laurent Vivier Signed-off-by: Richard Henderson --- target/m68k/m68k-semi.c | 281 +++++++--------------------------------- 1 file changed, 49 insertions(+), 232 deletions(-) diff --git a/target/m68k/m68k-semi.c b/target/m68k/m68k-semi.c index d0697ddbd1..586a801034 100644 --- a/target/m68k/m68k-semi.c +++ b/target/m68k/m68k-semi.c @@ -21,6 +21,7 @@ #include "cpu.h" #include "exec/gdbstub.h" +#include "semihosting/syscalls.h" #include "semihosting/softmmu-uaccess.h" #include "hw/boards.h" #include "qemu/log.h" @@ -40,56 +41,6 @@ #define HOSTED_ISATTY 12 #define HOSTED_SYSTEM 13 -static int translate_openflags(int flags) -{ - int hf; - - if (flags & GDB_O_WRONLY) - hf = O_WRONLY; - else if (flags & GDB_O_RDWR) - hf = O_RDWR; - else - hf = O_RDONLY; - - if (flags & GDB_O_APPEND) hf |= O_APPEND; - if (flags & GDB_O_CREAT) hf |= O_CREAT; - if (flags & GDB_O_TRUNC) hf |= O_TRUNC; - if (flags & GDB_O_EXCL) hf |= O_EXCL; - - return hf; -} - -static void translate_stat(CPUM68KState *env, target_ulong addr, struct stat *s) -{ - struct gdb_stat *p; - - p = lock_user(VERIFY_WRITE, addr, sizeof(struct gdb_stat), 0); - if (!p) { - /* FIXME - should this return an error code? */ - return; - } - p->gdb_st_dev = cpu_to_be32(s->st_dev); - p->gdb_st_ino = cpu_to_be32(s->st_ino); - p->gdb_st_mode = cpu_to_be32(s->st_mode); - p->gdb_st_nlink = cpu_to_be32(s->st_nlink); - p->gdb_st_uid = cpu_to_be32(s->st_uid); - p->gdb_st_gid = cpu_to_be32(s->st_gid); - p->gdb_st_rdev = cpu_to_be32(s->st_rdev); - p->gdb_st_size = cpu_to_be64(s->st_size); -#ifdef _WIN32 - /* Windows stat is missing some fields. */ - p->gdb_st_blksize = 0; - p->gdb_st_blocks = 0; -#else - p->gdb_st_blksize = cpu_to_be64(s->st_blksize); - p->gdb_st_blocks = cpu_to_be64(s->st_blocks); -#endif - p->gdb_st_atime = cpu_to_be32(s->st_atime); - p->gdb_st_mtime = cpu_to_be32(s->st_mtime); - p->gdb_st_ctime = cpu_to_be32(s->st_ctime); - unlock_user(p, addr, sizeof(struct gdb_stat)); -} - static void m68k_semi_u32_cb(CPUState *cs, uint64_t ret, int err) { M68kCPU *cpu = M68K_CPU(cs); @@ -129,248 +80,109 @@ static void m68k_semi_u64_cb(CPUState *cs, uint64_t ret, int err) */ #define GET_ARG(n) do { \ if (get_user_ual(arg ## n, args + (n) * 4)) { \ - result = -1; \ - errno = EFAULT; \ goto failed; \ } \ } while (0) +#define GET_ARG64(n) do { \ + if (get_user_ual(arg ## n, args + (n) * 4)) { \ + goto failed64; \ + } \ +} while (0) + + void do_m68k_semihosting(CPUM68KState *env, int nr) { CPUState *cs = env_cpu(env); uint32_t args; target_ulong arg0, arg1, arg2, arg3; - void *p; - void *q; - uint32_t len; - uint32_t result; args = env->dregs[1]; switch (nr) { case HOSTED_EXIT: gdb_exit(env->dregs[0]); exit(env->dregs[0]); + case HOSTED_OPEN: GET_ARG(0); GET_ARG(1); GET_ARG(2); GET_ARG(3); - if (use_gdb_syscalls()) { - gdb_do_syscall(m68k_semi_u32_cb, "open,%s,%x,%x", arg0, (int)arg1, - arg2, arg3); - return; - } else { - p = lock_user_string(arg0); - if (!p) { - /* FIXME - check error code? */ - result = -1; - } else { - result = open(p, translate_openflags(arg2), arg3); - unlock_user(p, arg0, 0); - } - } + semihost_sys_open(cs, m68k_semi_u32_cb, arg0, arg1, arg2, arg3); break; + case HOSTED_CLOSE: - { - /* Ignore attempts to close stdin/out/err. */ - GET_ARG(0); - int fd = arg0; - if (fd > 2) { - if (use_gdb_syscalls()) { - gdb_do_syscall(m68k_semi_u32_cb, "close,%x", arg0); - return; - } else { - result = close(fd); - } - } else { - result = 0; - } - break; - } + GET_ARG(0); + semihost_sys_close(cs, m68k_semi_u32_cb, arg0); + break; + case HOSTED_READ: GET_ARG(0); GET_ARG(1); GET_ARG(2); - len = arg2; - if (use_gdb_syscalls()) { - gdb_do_syscall(m68k_semi_u32_cb, "read,%x,%x,%x", - arg0, arg1, len); - return; - } else { - p = lock_user(VERIFY_WRITE, arg1, len, 0); - if (!p) { - /* FIXME - check error code? */ - result = -1; - } else { - result = read(arg0, p, len); - unlock_user(p, arg1, len); - } - } + semihost_sys_read(cs, m68k_semi_u32_cb, arg0, arg1, arg2); break; + case HOSTED_WRITE: GET_ARG(0); GET_ARG(1); GET_ARG(2); - len = arg2; - if (use_gdb_syscalls()) { - gdb_do_syscall(m68k_semi_u32_cb, "write,%x,%x,%x", - arg0, arg1, len); - return; - } else { - p = lock_user(VERIFY_READ, arg1, len, 1); - if (!p) { - /* FIXME - check error code? */ - result = -1; - } else { - result = write(arg0, p, len); - unlock_user(p, arg0, 0); - } - } + semihost_sys_write(cs, m68k_semi_u32_cb, arg0, arg1, arg2); break; + case HOSTED_LSEEK: - { - uint64_t off; - GET_ARG(0); - GET_ARG(1); - GET_ARG(2); - GET_ARG(3); - off = (uint32_t)arg2 | ((uint64_t)arg1 << 32); - if (use_gdb_syscalls()) { - gdb_do_syscall(m68k_semi_u64_cb, "fseek,%x,%lx,%x", - arg0, off, arg3); - } else { - off = lseek(arg0, off, arg3); - m68k_semi_u64_cb(cs, off, errno); - } - return; - } + GET_ARG64(0); + GET_ARG64(1); + GET_ARG64(2); + GET_ARG64(3); + semihost_sys_lseek(cs, m68k_semi_u64_cb, arg0, + deposit64(arg2, arg1, 32, 32), arg3); + break; + case HOSTED_RENAME: GET_ARG(0); GET_ARG(1); GET_ARG(2); GET_ARG(3); - if (use_gdb_syscalls()) { - gdb_do_syscall(m68k_semi_u32_cb, "rename,%s,%s", - arg0, (int)arg1, arg2, (int)arg3); - return; - } else { - p = lock_user_string(arg0); - q = lock_user_string(arg2); - if (!p || !q) { - /* FIXME - check error code? */ - result = -1; - } else { - result = rename(p, q); - } - unlock_user(p, arg0, 0); - unlock_user(q, arg2, 0); - } + semihost_sys_rename(cs, m68k_semi_u32_cb, arg0, arg1, arg2, arg3); break; + case HOSTED_UNLINK: GET_ARG(0); GET_ARG(1); - if (use_gdb_syscalls()) { - gdb_do_syscall(m68k_semi_u32_cb, "unlink,%s", - arg0, (int)arg1); - return; - } else { - p = lock_user_string(arg0); - if (!p) { - /* FIXME - check error code? */ - result = -1; - } else { - result = unlink(p); - unlock_user(p, arg0, 0); - } - } + semihost_sys_remove(cs, m68k_semi_u32_cb, arg0, arg1); break; + case HOSTED_STAT: GET_ARG(0); GET_ARG(1); GET_ARG(2); - if (use_gdb_syscalls()) { - gdb_do_syscall(m68k_semi_u32_cb, "stat,%s,%x", - arg0, (int)arg1, arg2); - return; - } else { - struct stat s; - p = lock_user_string(arg0); - if (!p) { - /* FIXME - check error code? */ - result = -1; - } else { - result = stat(p, &s); - unlock_user(p, arg0, 0); - } - if (result == 0) { - translate_stat(env, arg2, &s); - } - } + semihost_sys_stat(cs, m68k_semi_u32_cb, arg0, arg1, arg2); break; + case HOSTED_FSTAT: GET_ARG(0); GET_ARG(1); - if (use_gdb_syscalls()) { - gdb_do_syscall(m68k_semi_u32_cb, "fstat,%x,%x", - arg0, arg1); - return; - } else { - struct stat s; - result = fstat(arg0, &s); - if (result == 0) { - translate_stat(env, arg1, &s); - } - } + semihost_sys_fstat(cs, m68k_semi_u32_cb, arg0, arg1); break; + case HOSTED_GETTIMEOFDAY: GET_ARG(0); GET_ARG(1); - if (use_gdb_syscalls()) { - gdb_do_syscall(m68k_semi_u32_cb, "gettimeofday,%x,%x", - arg0, arg1); - return; - } else { - struct gdb_timeval *p; - int64_t rt = g_get_real_time(); - p = lock_user(VERIFY_WRITE, arg0, sizeof(struct gdb_timeval), 0); - if (!p) { - /* FIXME - check error code? */ - result = -1; - } else { - result = 0; - p->tv_sec = cpu_to_be32(rt / G_USEC_PER_SEC); - p->tv_usec = cpu_to_be64(rt % G_USEC_PER_SEC); - unlock_user(p, arg0, sizeof(struct gdb_timeval)); - } - } + semihost_sys_gettimeofday(cs, m68k_semi_u32_cb, arg0, arg1); break; + case HOSTED_ISATTY: GET_ARG(0); - if (use_gdb_syscalls()) { - gdb_do_syscall(m68k_semi_u32_cb, "isatty,%x", arg0); - return; - } else { - result = isatty(arg0); - } + semihost_sys_isatty(cs, m68k_semi_u32_cb, arg0); break; + case HOSTED_SYSTEM: GET_ARG(0); GET_ARG(1); - if (use_gdb_syscalls()) { - gdb_do_syscall(m68k_semi_u32_cb, "system,%s", - arg0, (int)arg1); - return; - } else { - p = lock_user_string(arg0); - if (!p) { - /* FIXME - check error code? */ - result = -1; - } else { - result = system(p); - unlock_user(p, arg0, 0); - } - } + semihost_sys_system(cs, m68k_semi_u32_cb, arg0, arg1); break; + case HOSTED_INIT_SIM: /* * FIXME: This is wrong for boards where RAM does not start at @@ -379,10 +191,15 @@ void do_m68k_semihosting(CPUM68KState *env, int nr) env->dregs[1] = current_machine->ram_size; env->aregs[7] = current_machine->ram_size; return; + default: cpu_abort(env_cpu(env), "Unsupported semihosting syscall %d\n", nr); - result = 0; + + failed: + m68k_semi_u32_cb(cs, -1, EFAULT); + break; + failed64: + m68k_semi_u64_cb(cs, -1, EFAULT); + break; } -failed: - m68k_semi_u32_cb(cs, result, errno); } From 7327e60237c36e9aa089141de547ca224ec5f3be Mon Sep 17 00:00:00 2001 From: Richard Henderson Date: Mon, 20 Jun 2022 15:22:14 -0700 Subject: [PATCH 04/11] target/m68k: Convert semihosting errno to gdb remote errno The semihosting abi used by m68k uses the gdb remote protocol filesys errnos. Acked-by: Laurent Vivier Signed-off-by: Richard Henderson --- target/m68k/m68k-semi.c | 33 +++++++++++++++++++++++++++++++-- 1 file changed, 31 insertions(+), 2 deletions(-) diff --git a/target/m68k/m68k-semi.c b/target/m68k/m68k-semi.c index 586a801034..87b1314925 100644 --- a/target/m68k/m68k-semi.c +++ b/target/m68k/m68k-semi.c @@ -41,6 +41,35 @@ #define HOSTED_ISATTY 12 #define HOSTED_SYSTEM 13 +static int host_to_gdb_errno(int err) +{ +#define E(X) case E##X: return GDB_E##X + switch (err) { + E(PERM); + E(NOENT); + E(INTR); + E(BADF); + E(ACCES); + E(FAULT); + E(BUSY); + E(EXIST); + E(NODEV); + E(NOTDIR); + E(ISDIR); + E(INVAL); + E(NFILE); + E(MFILE); + E(FBIG); + E(NOSPC); + E(SPIPE); + E(ROFS); + E(NAMETOOLONG); + default: + return GDB_EUNKNOWN; + } +#undef E +} + static void m68k_semi_u32_cb(CPUState *cs, uint64_t ret, int err) { M68kCPU *cpu = M68K_CPU(cs); @@ -48,7 +77,7 @@ static void m68k_semi_u32_cb(CPUState *cs, uint64_t ret, int err) target_ulong args = env->dregs[1]; if (put_user_u32(ret, args) || - put_user_u32(err, args + 4)) { + put_user_u32(host_to_gdb_errno(err), args + 4)) { /* * The m68k semihosting ABI does not provide any way to report this * error to the guest, so the best we can do is log it in qemu. @@ -67,7 +96,7 @@ static void m68k_semi_u64_cb(CPUState *cs, uint64_t ret, int err) target_ulong args = env->dregs[1]; if (put_user_u32(ret >> 32, args) || put_user_u32(ret, args + 4) || - put_user_u32(err, args + 8)) { + put_user_u32(host_to_gdb_errno(err), args + 8)) { /* No way to report this via m68k semihosting ABI; just log it */ qemu_log_mask(LOG_GUEST_ERROR, "m68k-semihosting: return value " "discarded because argument block not writable\n"); From 5202861b20d77b1d638da5f10af0f51ebcfc61bf Mon Sep 17 00:00:00 2001 From: Peter Maydell Date: Mon, 22 Aug 2022 15:12:24 +0100 Subject: [PATCH 05/11] semihosting: Allow optional use of semihosting from userspace MIME-Version: 1.0 Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 8bit Currently our semihosting implementations generally prohibit use of semihosting calls in system emulation from the guest userspace. This is a very long standing behaviour justified originally "to provide some semblance of security" (since code with access to the semihosting ABI can do things like read and write arbitrary files on the host system). However, it is sometimes useful to be able to run trusted guest code which performs semihosting calls from guest userspace, notably for test code. Add a command line suboption to the existing semihosting-config option group so that you can explicitly opt in to semihosting from guest userspace with -semihosting-config userspace=on (There is no equivalent option for the user-mode emulator, because there by definition all code runs in userspace and has access to semihosting already.) This commit adds the infrastructure for the command line option and adds a bool 'is_user' parameter to the function semihosting_userspace_enabled() that target code can use to check whether it should be permitting the semihosting call for userspace. It mechanically makes all the callsites pass 'false', so they continue checking "is semihosting enabled in general". Subsequent commits will make each target that implements semihosting honour the userspace=on option by passing the correct value and removing whatever "don't do this for userspace" checking they were doing by hand. Signed-off-by: Peter Maydell Acked-by: Alex Bennée Reviewed-by: Alistair Francis Reviewed-by: Philippe Mathieu-Daudé Reviewed-by: Richard Henderson Message-Id: <20220822141230.3658237-2-peter.maydell@linaro.org> Signed-off-by: Richard Henderson --- include/semihosting/semihost.h | 10 ++++++++-- qemu-options.hx | 11 +++++++++-- semihosting/config.c | 10 ++++++++-- softmmu/vl.c | 2 +- stubs/semihost.c | 2 +- target/arm/translate-a64.c | 2 +- target/arm/translate.c | 6 +++--- target/m68k/op_helper.c | 2 +- target/nios2/translate.c | 2 +- target/xtensa/translate.c | 6 +++--- 10 files changed, 36 insertions(+), 17 deletions(-) diff --git a/include/semihosting/semihost.h b/include/semihosting/semihost.h index 93a3c21b44..efd2efa25a 100644 --- a/include/semihosting/semihost.h +++ b/include/semihosting/semihost.h @@ -27,7 +27,7 @@ typedef enum SemihostingTarget { } SemihostingTarget; #ifdef CONFIG_USER_ONLY -static inline bool semihosting_enabled(void) +static inline bool semihosting_enabled(bool is_user) { return true; } @@ -52,7 +52,13 @@ static inline const char *semihosting_get_cmdline(void) return NULL; } #else /* !CONFIG_USER_ONLY */ -bool semihosting_enabled(void); +/** + * semihosting_enabled: + * @is_user: true if guest code is in usermode (i.e. not privileged) + * + * Return true if guest code is allowed to make semihosting calls. + */ +bool semihosting_enabled(bool is_user); SemihostingTarget semihosting_get_target(void); const char *semihosting_get_arg(int i); int semihosting_get_argc(void); diff --git a/qemu-options.hx b/qemu-options.hx index 31c04f7eea..1bb02363ab 100644 --- a/qemu-options.hx +++ b/qemu-options.hx @@ -4627,12 +4627,12 @@ SRST information about the facilities this enables. ERST DEF("semihosting-config", HAS_ARG, QEMU_OPTION_semihosting_config, - "-semihosting-config [enable=on|off][,target=native|gdb|auto][,chardev=id][,arg=str[,...]]\n" \ + "-semihosting-config [enable=on|off][,target=native|gdb|auto][,chardev=id][,userspace=on|off][,arg=str[,...]]\n" \ " semihosting configuration\n", QEMU_ARCH_ARM | QEMU_ARCH_M68K | QEMU_ARCH_XTENSA | QEMU_ARCH_MIPS | QEMU_ARCH_NIOS2 | QEMU_ARCH_RISCV) SRST -``-semihosting-config [enable=on|off][,target=native|gdb|auto][,chardev=id][,arg=str[,...]]`` +``-semihosting-config [enable=on|off][,target=native|gdb|auto][,chardev=id][,userspace=on|off][,arg=str[,...]]`` Enable and configure semihosting (ARM, M68K, Xtensa, MIPS, Nios II, RISC-V only). @@ -4659,6 +4659,13 @@ SRST Send the output to a chardev backend output for native or auto output when not in gdb + ``userspace=on|off`` + Allows code running in guest userspace to access the semihosting + interface. The default is that only privileged guest code can + make semihosting calls. Note that setting ``userspace=on`` should + only be used if all guest code is trusted (for example, in + bare-metal test case code). + ``arg=str1,arg=str2,...`` Allows the user to pass input arguments, and can be used multiple times to build up a list. The old-style diff --git a/semihosting/config.c b/semihosting/config.c index e171d4d6bc..89a1759687 100644 --- a/semihosting/config.c +++ b/semihosting/config.c @@ -34,6 +34,9 @@ QemuOptsList qemu_semihosting_config_opts = { { .name = "enable", .type = QEMU_OPT_BOOL, + }, { + .name = "userspace", + .type = QEMU_OPT_BOOL, }, { .name = "target", .type = QEMU_OPT_STRING, @@ -50,6 +53,7 @@ QemuOptsList qemu_semihosting_config_opts = { typedef struct SemihostingConfig { bool enabled; + bool userspace_enabled; SemihostingTarget target; char **argv; int argc; @@ -59,9 +63,9 @@ typedef struct SemihostingConfig { static SemihostingConfig semihosting; static const char *semihost_chardev; -bool semihosting_enabled(void) +bool semihosting_enabled(bool is_user) { - return semihosting.enabled; + return semihosting.enabled && (!is_user || semihosting.userspace_enabled); } SemihostingTarget semihosting_get_target(void) @@ -137,6 +141,8 @@ int qemu_semihosting_config_options(const char *optarg) if (opts != NULL) { semihosting.enabled = qemu_opt_get_bool(opts, "enable", true); + semihosting.userspace_enabled = qemu_opt_get_bool(opts, "userspace", + false); const char *target = qemu_opt_get(opts, "target"); /* setup of chardev is deferred until they are initialised */ semihost_chardev = qemu_opt_get(opts, "chardev"); diff --git a/softmmu/vl.c b/softmmu/vl.c index dea4005e47..263f029a8e 100644 --- a/softmmu/vl.c +++ b/softmmu/vl.c @@ -1822,7 +1822,7 @@ static void qemu_apply_machine_options(QDict *qdict) { object_set_properties_from_keyval(OBJECT(current_machine), qdict, false, &error_fatal); - if (semihosting_enabled() && !semihosting_get_argc()) { + if (semihosting_enabled(false) && !semihosting_get_argc()) { /* fall back to the -kernel/-append */ semihosting_arg_fallback(current_machine->kernel_filename, current_machine->kernel_cmdline); } diff --git a/stubs/semihost.c b/stubs/semihost.c index f486651afb..d65c9fd5dc 100644 --- a/stubs/semihost.c +++ b/stubs/semihost.c @@ -23,7 +23,7 @@ QemuOptsList qemu_semihosting_config_opts = { }; /* Queries to config status default to off */ -bool semihosting_enabled(void) +bool semihosting_enabled(bool is_user) { return false; } diff --git a/target/arm/translate-a64.c b/target/arm/translate-a64.c index 163df8c615..3decc8da57 100644 --- a/target/arm/translate-a64.c +++ b/target/arm/translate-a64.c @@ -2219,7 +2219,7 @@ static void disas_exc(DisasContext *s, uint32_t insn) * it is required for halting debug disabled: it will UNDEF. * Secondly, "HLT 0xf000" is the A64 semihosting syscall instruction. */ - if (semihosting_enabled() && imm16 == 0xf000) { + if (semihosting_enabled(false) && imm16 == 0xf000) { #ifndef CONFIG_USER_ONLY /* In system mode, don't allow userspace access to semihosting, * to provide some semblance of security (and for consistency diff --git a/target/arm/translate.c b/target/arm/translate.c index 9474e4b44b..b1e013270d 100644 --- a/target/arm/translate.c +++ b/target/arm/translate.c @@ -1169,7 +1169,7 @@ static inline void gen_hlt(DisasContext *s, int imm) * semihosting, to provide some semblance of security * (and for consistency with our 32-bit semihosting). */ - if (semihosting_enabled() && + if (semihosting_enabled(false) && #ifndef CONFIG_USER_ONLY s->current_el != 0 && #endif @@ -6556,7 +6556,7 @@ static bool trans_BKPT(DisasContext *s, arg_BKPT *a) /* BKPT is OK with ECI set and leaves it untouched */ s->eci_handled = true; if (arm_dc_feature(s, ARM_FEATURE_M) && - semihosting_enabled() && + semihosting_enabled(false) && #ifndef CONFIG_USER_ONLY !IS_USER(s) && #endif @@ -8764,7 +8764,7 @@ static bool trans_SVC(DisasContext *s, arg_SVC *a) { const uint32_t semihost_imm = s->thumb ? 0xab : 0x123456; - if (!arm_dc_feature(s, ARM_FEATURE_M) && semihosting_enabled() && + if (!arm_dc_feature(s, ARM_FEATURE_M) && semihosting_enabled(false) && #ifndef CONFIG_USER_ONLY !IS_USER(s) && #endif diff --git a/target/m68k/op_helper.c b/target/m68k/op_helper.c index d9937ca8dc..4b3dfec130 100644 --- a/target/m68k/op_helper.c +++ b/target/m68k/op_helper.c @@ -203,7 +203,7 @@ static void cf_interrupt_all(CPUM68KState *env, int is_hw) cf_rte(env); return; case EXCP_HALT_INSN: - if (semihosting_enabled() + if (semihosting_enabled(false) && (env->sr & SR_S) != 0 && (env->pc & 3) == 0 && cpu_lduw_code(env, env->pc - 4) == 0x4e71 diff --git a/target/nios2/translate.c b/target/nios2/translate.c index c588e8e885..ff631a42f6 100644 --- a/target/nios2/translate.c +++ b/target/nios2/translate.c @@ -818,7 +818,7 @@ static void gen_break(DisasContext *dc, uint32_t code, uint32_t flags) #ifndef CONFIG_USER_ONLY /* The semihosting instruction is "break 1". */ R_TYPE(instr, code); - if (semihosting_enabled() && instr.imm5 == 1) { + if (semihosting_enabled(false) && instr.imm5 == 1) { t_gen_helper_raise_exception(dc, EXCP_SEMIHOST); return; } diff --git a/target/xtensa/translate.c b/target/xtensa/translate.c index 8b864ef925..afae8a1bea 100644 --- a/target/xtensa/translate.c +++ b/target/xtensa/translate.c @@ -2366,9 +2366,9 @@ static uint32_t test_exceptions_simcall(DisasContext *dc, bool ill = true; #else /* Between RE.2 and RE.3 simcall opcode's become nop for the hardware. */ - bool ill = dc->config->hw_version <= 250002 && !semihosting_enabled(); + bool ill = dc->config->hw_version <= 250002 && !semihosting_enabled(false); #endif - if (ill || !semihosting_enabled()) { + if (ill || !semihosting_enabled(false)) { qemu_log_mask(LOG_GUEST_ERROR, "SIMCALL but semihosting is disabled\n"); } return ill ? XTENSA_OP_ILL : 0; @@ -2378,7 +2378,7 @@ static void translate_simcall(DisasContext *dc, const OpcodeArg arg[], const uint32_t par[]) { #ifndef CONFIG_USER_ONLY - if (semihosting_enabled()) { + if (semihosting_enabled(false)) { gen_helper_simcall(cpu_env); } #endif From 19b26317e9eb0c4dfd42e341ba7c4474c6d53ff9 Mon Sep 17 00:00:00 2001 From: Peter Maydell Date: Mon, 22 Aug 2022 15:12:25 +0100 Subject: [PATCH 06/11] target/arm: Honour -semihosting-config userspace=on Honour the commandline -semihosting-config userspace=on option, instead of never permitting userspace semihosting calls in system emulation mode, by passing the correct value to the is_userspace argument of semihosting_enabled(), instead of manually checking and always forbidding semihosting if the guest is in userspace and this isn't the linux-user build. Signed-off-by: Peter Maydell Reviewed-by: Richard Henderson Message-Id: <20220822141230.3658237-3-peter.maydell@linaro.org> Signed-off-by: Richard Henderson --- target/arm/translate-a64.c | 12 +----------- target/arm/translate.c | 16 ++++------------ 2 files changed, 5 insertions(+), 23 deletions(-) diff --git a/target/arm/translate-a64.c b/target/arm/translate-a64.c index 3decc8da57..9bed336b47 100644 --- a/target/arm/translate-a64.c +++ b/target/arm/translate-a64.c @@ -2219,17 +2219,7 @@ static void disas_exc(DisasContext *s, uint32_t insn) * it is required for halting debug disabled: it will UNDEF. * Secondly, "HLT 0xf000" is the A64 semihosting syscall instruction. */ - if (semihosting_enabled(false) && imm16 == 0xf000) { -#ifndef CONFIG_USER_ONLY - /* In system mode, don't allow userspace access to semihosting, - * to provide some semblance of security (and for consistency - * with our 32-bit semihosting). - */ - if (s->current_el == 0) { - unallocated_encoding(s); - break; - } -#endif + if (semihosting_enabled(s->current_el == 0) && imm16 == 0xf000) { gen_exception_internal_insn(s, s->pc_curr, EXCP_SEMIHOST); } else { unallocated_encoding(s); diff --git a/target/arm/translate.c b/target/arm/translate.c index b1e013270d..5aaccbbf71 100644 --- a/target/arm/translate.c +++ b/target/arm/translate.c @@ -1169,10 +1169,7 @@ static inline void gen_hlt(DisasContext *s, int imm) * semihosting, to provide some semblance of security * (and for consistency with our 32-bit semihosting). */ - if (semihosting_enabled(false) && -#ifndef CONFIG_USER_ONLY - s->current_el != 0 && -#endif + if (semihosting_enabled(s->current_el != 0) && (imm == (s->thumb ? 0x3c : 0xf000))) { gen_exception_internal_insn(s, s->pc_curr, EXCP_SEMIHOST); return; @@ -6556,10 +6553,7 @@ static bool trans_BKPT(DisasContext *s, arg_BKPT *a) /* BKPT is OK with ECI set and leaves it untouched */ s->eci_handled = true; if (arm_dc_feature(s, ARM_FEATURE_M) && - semihosting_enabled(false) && -#ifndef CONFIG_USER_ONLY - !IS_USER(s) && -#endif + semihosting_enabled(s->current_el == 0) && (a->imm == 0xab)) { gen_exception_internal_insn(s, s->pc_curr, EXCP_SEMIHOST); } else { @@ -8764,10 +8758,8 @@ static bool trans_SVC(DisasContext *s, arg_SVC *a) { const uint32_t semihost_imm = s->thumb ? 0xab : 0x123456; - if (!arm_dc_feature(s, ARM_FEATURE_M) && semihosting_enabled(false) && -#ifndef CONFIG_USER_ONLY - !IS_USER(s) && -#endif + if (!arm_dc_feature(s, ARM_FEATURE_M) && + semihosting_enabled(s->current_el == 0) && (a->imm == semihost_imm)) { gen_exception_internal_insn(s, s->pc_curr, EXCP_SEMIHOST); } else { From a52417e1eeb4501993e29145d16faac59e8465ca Mon Sep 17 00:00:00 2001 From: Peter Maydell Date: Mon, 22 Aug 2022 15:12:26 +0100 Subject: [PATCH 07/11] target/m68k: Honour -semihosting-config userspace=on Honour the commandline -semihosting-config userspace=on option, instead of never permitting userspace semihosting calls in system emulation mode, by passing the correct value to the is_userspace argument of semihosting_enabled(), instead of manually checking and always forbidding semihosting if the guest is in userspace. (Note that target/m68k doesn't support semihosting at all in the linux-user build.) Signed-off-by: Peter Maydell Reviewed-by: Laurent Vivier Reviewed-by: Richard Henderson Message-Id: <20220822141230.3658237-4-peter.maydell@linaro.org> Signed-off-by: Richard Henderson --- target/m68k/op_helper.c | 3 +-- 1 file changed, 1 insertion(+), 2 deletions(-) diff --git a/target/m68k/op_helper.c b/target/m68k/op_helper.c index 4b3dfec130..a96a034050 100644 --- a/target/m68k/op_helper.c +++ b/target/m68k/op_helper.c @@ -203,8 +203,7 @@ static void cf_interrupt_all(CPUM68KState *env, int is_hw) cf_rte(env); return; case EXCP_HALT_INSN: - if (semihosting_enabled(false) - && (env->sr & SR_S) != 0 + if (semihosting_enabled((env->sr & SR_S) == 0) && (env->pc & 3) == 0 && cpu_lduw_code(env, env->pc - 4) == 0x4e71 && cpu_ldl_code(env, env->pc) == 0x4e7bf000) { From b35d74015b0262260b7dbb75c80ea85aeebab89b Mon Sep 17 00:00:00 2001 From: Peter Maydell Date: Mon, 22 Aug 2022 15:12:27 +0100 Subject: [PATCH 08/11] target/mips: Honour -semihosting-config userspace=on MIME-Version: 1.0 Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 8bit Honour the commandline -semihosting-config userspace=on option, instead of always permitting userspace semihosting calls in system emulation mode, by passing the correct value to the is_userspace argument of semihosting_enabled(). Note that this is a behaviour change: if the user wants to do semihosting calls from userspace they must now specifically enable them on the command line. MIPS semihosting is not implemented for linux-user builds. Signed-off-by: Peter Maydell Reviewed-by: Philippe Mathieu-Daudé Reviewed-by: Richard Henderson Message-Id: <20220822141230.3658237-5-peter.maydell@linaro.org> Signed-off-by: Richard Henderson --- target/mips/tcg/micromips_translate.c.inc | 6 +++--- target/mips/tcg/mips16e_translate.c.inc | 2 +- target/mips/tcg/nanomips_translate.c.inc | 4 ++-- target/mips/tcg/translate.c | 9 +++++---- 4 files changed, 11 insertions(+), 10 deletions(-) diff --git a/target/mips/tcg/micromips_translate.c.inc b/target/mips/tcg/micromips_translate.c.inc index b2c696f891..632895cc9e 100644 --- a/target/mips/tcg/micromips_translate.c.inc +++ b/target/mips/tcg/micromips_translate.c.inc @@ -825,7 +825,7 @@ static void gen_pool16c_insn(DisasContext *ctx) generate_exception_break(ctx, extract32(ctx->opcode, 0, 4)); break; case SDBBP16: - if (is_uhi(extract32(ctx->opcode, 0, 4))) { + if (is_uhi(ctx, extract32(ctx->opcode, 0, 4))) { ctx->base.is_jmp = DISAS_SEMIHOST; } else { /* @@ -941,7 +941,7 @@ static void gen_pool16c_r6_insn(DisasContext *ctx) break; case R6_SDBBP16: /* SDBBP16 */ - if (is_uhi(extract32(ctx->opcode, 6, 4))) { + if (is_uhi(ctx, extract32(ctx->opcode, 6, 4))) { ctx->base.is_jmp = DISAS_SEMIHOST; } else { if (ctx->hflags & MIPS_HFLAG_SBRI) { @@ -1310,7 +1310,7 @@ static void gen_pool32axf(CPUMIPSState *env, DisasContext *ctx, int rt, int rs) generate_exception_end(ctx, EXCP_SYSCALL); break; case SDBBP: - if (is_uhi(extract32(ctx->opcode, 16, 10))) { + if (is_uhi(ctx, extract32(ctx->opcode, 16, 10))) { ctx->base.is_jmp = DISAS_SEMIHOST; } else { check_insn(ctx, ISA_MIPS_R1); diff --git a/target/mips/tcg/mips16e_translate.c.inc b/target/mips/tcg/mips16e_translate.c.inc index 7568933e23..918b15d55c 100644 --- a/target/mips/tcg/mips16e_translate.c.inc +++ b/target/mips/tcg/mips16e_translate.c.inc @@ -951,7 +951,7 @@ static int decode_ase_mips16e(CPUMIPSState *env, DisasContext *ctx) } break; case RR_SDBBP: - if (is_uhi(extract32(ctx->opcode, 5, 6))) { + if (is_uhi(ctx, extract32(ctx->opcode, 5, 6))) { ctx->base.is_jmp = DISAS_SEMIHOST; } else { /* diff --git a/target/mips/tcg/nanomips_translate.c.inc b/target/mips/tcg/nanomips_translate.c.inc index b3aff22c18..812c111e3c 100644 --- a/target/mips/tcg/nanomips_translate.c.inc +++ b/target/mips/tcg/nanomips_translate.c.inc @@ -3694,7 +3694,7 @@ static int decode_nanomips_32_48_opc(CPUMIPSState *env, DisasContext *ctx) generate_exception_end(ctx, EXCP_BREAK); break; case NM_SDBBP: - if (is_uhi(extract32(ctx->opcode, 0, 19))) { + if (is_uhi(ctx, extract32(ctx->opcode, 0, 19))) { ctx->base.is_jmp = DISAS_SEMIHOST; } else { if (ctx->hflags & MIPS_HFLAG_SBRI) { @@ -4633,7 +4633,7 @@ static int decode_isa_nanomips(CPUMIPSState *env, DisasContext *ctx) generate_exception_end(ctx, EXCP_BREAK); break; case NM_SDBBP16: - if (is_uhi(extract32(ctx->opcode, 0, 3))) { + if (is_uhi(ctx, extract32(ctx->opcode, 0, 3))) { ctx->base.is_jmp = DISAS_SEMIHOST; } else { if (ctx->hflags & MIPS_HFLAG_SBRI) { diff --git a/target/mips/tcg/translate.c b/target/mips/tcg/translate.c index 0d936e2648..c3f92ea652 100644 --- a/target/mips/tcg/translate.c +++ b/target/mips/tcg/translate.c @@ -12082,12 +12082,13 @@ static void gen_cache_operation(DisasContext *ctx, uint32_t op, int base, tcg_temp_free_i32(t0); } -static inline bool is_uhi(int sdbbp_code) +static inline bool is_uhi(DisasContext *ctx, int sdbbp_code) { #ifdef CONFIG_USER_ONLY return false; #else - return semihosting_enabled() && sdbbp_code == 1; + bool is_user = (ctx->hflags & MIPS_HFLAG_KSU) == MIPS_HFLAG_UM; + return semihosting_enabled(is_user) && sdbbp_code == 1; #endif } @@ -13898,7 +13899,7 @@ static void decode_opc_special_r6(CPUMIPSState *env, DisasContext *ctx) } break; case R6_OPC_SDBBP: - if (is_uhi(extract32(ctx->opcode, 6, 20))) { + if (is_uhi(ctx, extract32(ctx->opcode, 6, 20))) { ctx->base.is_jmp = DISAS_SEMIHOST; } else { if (ctx->hflags & MIPS_HFLAG_SBRI) { @@ -14310,7 +14311,7 @@ static void decode_opc_special2_legacy(CPUMIPSState *env, DisasContext *ctx) gen_cl(ctx, op1, rd, rs); break; case OPC_SDBBP: - if (is_uhi(extract32(ctx->opcode, 6, 20))) { + if (is_uhi(ctx, extract32(ctx->opcode, 6, 20))) { ctx->base.is_jmp = DISAS_SEMIHOST; } else { /* From cab9f19370b5e26afbc7f62e08293507bf2a5f6b Mon Sep 17 00:00:00 2001 From: Peter Maydell Date: Mon, 22 Aug 2022 15:12:28 +0100 Subject: [PATCH 09/11] target/nios2: Honour -semihosting-config userspace=on Honour the commandline -semihosting-config userspace=on option, instead of always permitting userspace semihosting calls in system emulation mode, by passing the correct value to the is_userspace argument of semihosting_enabled(). Note that this is a behaviour change: if the user wants to do semihosting calls from userspace they must now specifically enable them on the command line. nios2 semihosting is not implemented for linux-user builds. Signed-off-by: Peter Maydell Reviewed-by: Richard Henderson Message-Id: <20220822141230.3658237-6-peter.maydell@linaro.org> Signed-off-by: Richard Henderson --- target/nios2/translate.c | 3 ++- 1 file changed, 2 insertions(+), 1 deletion(-) diff --git a/target/nios2/translate.c b/target/nios2/translate.c index ff631a42f6..8dc0a32c6c 100644 --- a/target/nios2/translate.c +++ b/target/nios2/translate.c @@ -817,8 +817,9 @@ static void gen_break(DisasContext *dc, uint32_t code, uint32_t flags) { #ifndef CONFIG_USER_ONLY /* The semihosting instruction is "break 1". */ + bool is_user = FIELD_EX32(dc->tb_flags, TBFLAGS, U); R_TYPE(instr, code); - if (semihosting_enabled(false) && instr.imm5 == 1) { + if (semihosting_enabled(is_user) && instr.imm5 == 1) { t_gen_helper_raise_exception(dc, EXCP_SEMIHOST); return; } From 870ab98bee4312caf0ced42999e295f741aba853 Mon Sep 17 00:00:00 2001 From: Peter Maydell Date: Mon, 22 Aug 2022 15:12:29 +0100 Subject: [PATCH 10/11] target/xtensa: Honour -semihosting-config userspace=on MIME-Version: 1.0 Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 8bit Honour the commandline -semihosting-config userspace=on option, instead of always permitting userspace semihosting calls in system emulation mode, by passing the correct value to the is_userspace argument of semihosting_enabled(). Note that this is a behaviour change: if the user wants to do semihosting calls from userspace they must now specifically enable them on the command line. xtensa semihosting is not implemented for linux-user builds. Signed-off-by: Peter Maydell Acked-by: Max Filippov Reviewed-by: Philippe Mathieu-Daudé Reviewed-by: Richard Henderson Message-Id: <20220822141230.3658237-7-peter.maydell@linaro.org> Signed-off-by: Richard Henderson --- target/xtensa/translate.c | 7 ++++--- 1 file changed, 4 insertions(+), 3 deletions(-) diff --git a/target/xtensa/translate.c b/target/xtensa/translate.c index afae8a1bea..bdd4690a5c 100644 --- a/target/xtensa/translate.c +++ b/target/xtensa/translate.c @@ -2362,13 +2362,14 @@ static uint32_t test_exceptions_simcall(DisasContext *dc, const OpcodeArg arg[], const uint32_t par[]) { + bool is_semi = semihosting_enabled(dc->cring != 0); #ifdef CONFIG_USER_ONLY bool ill = true; #else /* Between RE.2 and RE.3 simcall opcode's become nop for the hardware. */ - bool ill = dc->config->hw_version <= 250002 && !semihosting_enabled(false); + bool ill = dc->config->hw_version <= 250002 && !is_semi; #endif - if (ill || !semihosting_enabled(false)) { + if (ill || !is_semi) { qemu_log_mask(LOG_GUEST_ERROR, "SIMCALL but semihosting is disabled\n"); } return ill ? XTENSA_OP_ILL : 0; @@ -2378,7 +2379,7 @@ static void translate_simcall(DisasContext *dc, const OpcodeArg arg[], const uint32_t par[]) { #ifndef CONFIG_USER_ONLY - if (semihosting_enabled(false)) { + if (semihosting_enabled(dc->cring != 0)) { gen_helper_simcall(cpu_env); } #endif From 7d7fb11615809839ff858328134c6a0abad27ea4 Mon Sep 17 00:00:00 2001 From: Peter Maydell Date: Mon, 22 Aug 2022 15:12:30 +0100 Subject: [PATCH 11/11] target/riscv: Honour -semihosting-config userspace=on and enable=on The riscv target incorrectly enabled semihosting always, whether the user asked for it or not. Call semihosting_enabled() passing the correct value to the is_userspace argument, which fixes this and also handles the userspace=on argument. Because we do this at translate time, we no longer need to check the privilege level in riscv_cpu_do_interrupt(). Note that this is a behaviour change: we used to default to semihosting being enabled, and now the user must pass "-semihosting-config enable=on" if they want it. Signed-off-by: Peter Maydell Reviewed-by: Richard Henderson Reviewed-by: Alistair Francis Message-Id: <20220822141230.3658237-8-peter.maydell@linaro.org> Signed-off-by: Richard Henderson --- target/riscv/cpu_helper.c | 9 +++------ target/riscv/insn_trans/trans_privileged.c.inc | 3 ++- target/riscv/translate.c | 1 + 3 files changed, 6 insertions(+), 7 deletions(-) diff --git a/target/riscv/cpu_helper.c b/target/riscv/cpu_helper.c index 67e4c0efd2..278d163803 100644 --- a/target/riscv/cpu_helper.c +++ b/target/riscv/cpu_helper.c @@ -1589,12 +1589,9 @@ void riscv_cpu_do_interrupt(CPUState *cs) target_ulong mtval2 = 0; if (cause == RISCV_EXCP_SEMIHOST) { - if (env->priv >= PRV_S) { - do_common_semihosting(cs); - env->pc += 4; - return; - } - cause = RISCV_EXCP_BREAKPOINT; + do_common_semihosting(cs); + env->pc += 4; + return; } if (!async) { diff --git a/target/riscv/insn_trans/trans_privileged.c.inc b/target/riscv/insn_trans/trans_privileged.c.inc index 46f96ad74d..3281408a87 100644 --- a/target/riscv/insn_trans/trans_privileged.c.inc +++ b/target/riscv/insn_trans/trans_privileged.c.inc @@ -52,7 +52,8 @@ static bool trans_ebreak(DisasContext *ctx, arg_ebreak *a) * that no exception will be raised when fetching them. */ - if ((pre_addr & TARGET_PAGE_MASK) == (post_addr & TARGET_PAGE_MASK)) { + if (semihosting_enabled(ctx->mem_idx < PRV_S) && + (pre_addr & TARGET_PAGE_MASK) == (post_addr & TARGET_PAGE_MASK)) { pre = opcode_at(&ctx->base, pre_addr); ebreak = opcode_at(&ctx->base, ebreak_addr); post = opcode_at(&ctx->base, post_addr); diff --git a/target/riscv/translate.c b/target/riscv/translate.c index 8925a44c6e..db123da5ec 100644 --- a/target/riscv/translate.c +++ b/target/riscv/translate.c @@ -28,6 +28,7 @@ #include "exec/translator.h" #include "exec/log.h" +#include "semihosting/semihost.h" #include "instmap.h" #include "internals.h"