kvm: Make command line to be placed at predefined address

We support only 0x202 boot protocol at moment so that kernel command line is
copied into predefined address.

Reported-by: Pekka Enberg <penberg@cs.helsinki.fi>
Signed-off-by: Cyrill Gorcunov <gorcunov@gmail.com>
Signed-off-by: Pekka Enberg <penberg@cs.helsinki.fi>

diff --git a/tools/kvm/kvm.c b/tools/kvm/kvm.c
index 11dec87ef0e5093b515e3299a1c807f483e494fb..b48ef4037250d31100403feffef29c92f07950cc 100644 (file)
--- a/tools/kvm/kvm.c
+++ b/tools/kvm/kvm.c
@@ -176,6 +176,9 @@ void kvm__enable_singlestep(struct kvm *self)
 #define BOOT_LOADER_SELECTOR   0x1000
 #define BOOT_LOADER_IP         0x0000
 #define BOOT_LOADER_SP         0x8000
+#define BOOT_CMDLINE_OFFSET    0x20000
+
+#define BOOT_PROTOCOL_REQUIRED 0x202
 
 static int load_flat_binary(struct kvm *self, int fd)
 {
@@ -213,7 +216,7 @@ static bool load_bzimage(struct kvm *self, int fd, const char *kernel_cmdline)
        struct boot_params boot;
        unsigned long setup_sects;
        unsigned int intr_addr;
-       size_t cmdline_size, cmdline_offset;
+       size_t cmdline_size;
        ssize_t setup_size;
        void *p;
        int nr;
@@ -231,7 +234,7 @@ static bool load_bzimage(struct kvm *self, int fd, const char *kernel_cmdline)
         if (memcmp(&boot.hdr.header, BZIMAGE_MAGIC, strlen(BZIMAGE_MAGIC)) != 0)
                return false;
 
-       if (boot.hdr.version < 0x0200) {
+       if (boot.hdr.version < BOOT_PROTOCOL_REQUIRED) {
                warning("Too old kernel");
                return false;
        }
@@ -254,37 +257,17 @@ static bool load_bzimage(struct kvm *self, int fd, const char *kernel_cmdline)
        while ((nr = read(fd, p, 65536)) > 0)
                p += nr;
 
-       if (boot.hdr.version < 0x0206)
-               boot.hdr.cmdline_size = 256;
-
        if (kernel_cmdline) {
                cmdline_size = strlen(kernel_cmdline) + 1;
                if (cmdline_size > boot.hdr.cmdline_size)
                        cmdline_size = boot.hdr.cmdline_size;
-       } else
-               cmdline_size = 0;
-               
-
-       if (boot.hdr.version < 0x0202 || !(boot.hdr.loadflags & 0x01))
-               cmdline_offset = (0x9ff0 - cmdline_size) & ~15;
-       else
-               cmdline_offset = 0x10000;
-
-       if (kernel_cmdline) {
-               p = guest_flat_to_host(self, cmdline_offset);
-               memset(p, 0, cmdline_size);
-               strcpy(p, kernel_cmdline);
-       }
 
-       if (boot.hdr.version >= 0x0200) {
-               if (boot.hdr.version >= 0x0202) {
-                       boot.hdr.cmd_line_ptr =
-                               (BOOT_LOADER_SELECTOR << 4) + cmdline_offset;
-               } else if (boot.hdr.version >= 0x0201) {
-                       boot.hdr.heap_end_ptr = cmdline_offset - 0x0200;
-                       boot.hdr.loadflags |= CAN_USE_HEAP;
-               }
+               p = guest_flat_to_host(self, BOOT_CMDLINE_OFFSET);
+               memset(p, 0, boot.hdr.cmdline_size);
+               memcpy(p, kernel_cmdline, cmdline_size - 1);
 
+               p = guest_real_to_host(self, BOOT_LOADER_SELECTOR, 0x228);
+               *(unsigned long *)p = BOOT_CMDLINE_OFFSET;
        }
 
        self->boot_selector     = BOOT_LOADER_SELECTOR;