diff options
| -rw-r--r-- | .gitignore | 1 | ||||
| -rw-r--r-- | Makefile | 7 | ||||
| -rw-r--r-- | stage3/shell.c | 35 | ||||
| -rw-r--r-- | stage3/watchdog.lua | 73 |
4 files changed, 113 insertions, 3 deletions
@@ -7,6 +7,7 @@ .version-* bx_enh_dbg.ini stage3/isr.asm +stage3/watchdog.asm fs.tar stage3/version.c stage3/font_builtin.c @@ -34,7 +34,8 @@ STAGE3_C = \ STAGE3 = $(STAGE3_C) \ stage3/isr.o \ stage3/yield.o \ - stage3/paging.o + stage3/paging.o \ + stage3/watchdog.o PAD_BOUNDARY = pad() { truncate -s $$(echo "($$(du -b $$1 | cut -f1)+$$2-1)/$$2*$$2" | bc) $$1; }; pad DISAS = objdump -b binary -D -M intel -m i386:x86-64 stage3.bin --adjust-vma 0x9000 @@ -80,8 +81,8 @@ GIT_VERSION := $(shell git describe --tags 2>/dev/null || git rev-parse --short stage3/version.c: .version-$(GIT_VERSION) echo -e "#include \"def.h\"\nstr version = S(\"$(GIT_VERSION)\");" > $@ -stage3/isr.asm: stage3/isr.lua - lua stage3/isr.lua > stage3/isr.asm +stage3/%.asm: stage3/%.lua + lua $< > $@ stage3/font.c: stage3/font_builtin.c diff --git a/stage3/shell.c b/stage3/shell.c index 7341eea..5b79e58 100644 --- a/stage3/shell.c +++ b/stage3/shell.c @@ -267,6 +267,40 @@ void cmd_cheese(str arg) free(texture); } +struct __attribute__((packed)) { + u64 reg; + u64 to; + u64 from; +} watchdog_err; + +void watchdog(); + +static void cmd_watchdog(str arg) +{ + (void) arg; + + str regs[] = { + S("rax"), S("rbx"), + S("rcx"), S("rdx"), + S("rdi"), S("rsi"), + S("rbp"), S("rsp"), + S("r8"), S("r9"), + S("r10"), S("r11"), + S("r12"), S("r13"), + S("r14"), S("r15"), + }; + + watchdog(); + + print(S("watchdog: register ")); + print(regs[watchdog_err.reg]); + print(S(" changed from ")); + print_hex(watchdog_err.from); + print(S(" to ")); + print_hex(watchdog_err.to); + print(S("\n")); +} + typedef struct { str name; void (*fn)(str arg); @@ -287,6 +321,7 @@ static command registry[] = { { S("ls"), &cmd_ls }, { S("shutdown"), &cmd_shutdown }, { S("cheese"), &cmd_cheese }, + { S("watchdog"), &cmd_watchdog }, }; void shell_run_cmd(str cmd) diff --git a/stage3/watchdog.lua b/stage3/watchdog.lua new file mode 100644 index 0000000..dac4d57 --- /dev/null +++ b/stage3/watchdog.lua @@ -0,0 +1,73 @@ +local regs = { + "rax", "rbx", + "rcx", "rdx", + "rdi", "rsi", + "rbp", "rsp", + "r8", "r9", + "r10", "r11", + "r12", "r13", + "r14", "r15", +} + +print("global watchdog") +print("extern rand, watchdog_err") + +print("regs_backup: resq 16") +print("regs_rand: resq 16") + +print("watchdog:") + +local function iter_regs(f) + for i, r in ipairs(regs) do + f(i-1, r) + end +end + +-- backup registers +iter_regs(function(i, r) print("mov [regs_backup+" .. (8*i) .. "], " .. r) end) + +-- populate random table +iter_regs(function(i) print("xor rax, rax\ncall rand\nmov [regs_rand+" .. (8*i) .. "], rax") end) + +-- read registers from random table +iter_regs(function(i, r) + if r == "rsp" then + print("mov [regs_rand+" .. (8*i) .. "], rsp") + else + print("mov " .. r .. ", [regs_rand+" .. (8*i) .. "]") + end +end) + +print(".loop:") + +-- wait for interrupts +print("hlt") + +-- check and jump if changed +iter_regs(function(i, r) + print("cmp " .. r .. ", [regs_rand+" .. (8*i) .. "]") + print("jne .ch_" .. r) +end) + +print("jmp .loop") + +-- write error and return +iter_regs(function(i, r) + print(".ch_" .. r .. ":") + print("mov qword[watchdog_err], " .. i) + print("mov qword[watchdog_err+8], " .. r) + print("mov rax, [regs_rand+" .. (8*i) .. "]") + print("mov qword[watchdog_err+16], rax") + print("jmp .ret") +end) + +print(".ret:") + +-- restore registers +iter_regs(function(i, r) + if r ~= "rsp" then + print("mov " .. r .. ", [regs_backup+" .. (8*i) .. "]") + end +end) + +print("ret") |