* [Qemu-devel] [PATCH v5 0/2] aarch64: Allow -kernel option to take a gzip-compressed kernel.
@ 2014-08-04 11:47 Richard W.M. Jones
2014-08-04 11:47 ` [Qemu-devel] [PATCH v5 1/2] loader: Add load_image_gzipped function Richard W.M. Jones
2014-08-04 11:47 ` [Qemu-devel] [PATCH v5 2/2] aarch64: Allow -kernel option to take a gzip-compressed kernel Richard W.M. Jones
0 siblings, 2 replies; 7+ messages in thread
From: Richard W.M. Jones @ 2014-08-04 11:47 UTC (permalink / raw)
To: qemu-devel; +Cc: peter.maydell, peter.crosthwaite
Changes since v4:
- Split the patch into a generic loader part, and specific arm64
support.
- There is now a specific limit for the gzip loader, plus a comment
to indicate that it's just there to stop an excessive malloc. The
limit is now decoupled (and larger) than the u-boot limit, since
this function might be used for non-kernels in future.
- Remove comment about aarch64 in generic code.
Rich.
^ permalink raw reply [flat|nested] 7+ messages in thread
* [Qemu-devel] [PATCH v5 1/2] loader: Add load_image_gzipped function.
2014-08-04 11:47 [Qemu-devel] [PATCH v5 0/2] aarch64: Allow -kernel option to take a gzip-compressed kernel Richard W.M. Jones
@ 2014-08-04 11:47 ` Richard W.M. Jones
2014-08-05 9:52 ` Alex Bennée
2014-08-05 9:57 ` Alex Bennée
2014-08-04 11:47 ` [Qemu-devel] [PATCH v5 2/2] aarch64: Allow -kernel option to take a gzip-compressed kernel Richard W.M. Jones
1 sibling, 2 replies; 7+ messages in thread
From: Richard W.M. Jones @ 2014-08-04 11:47 UTC (permalink / raw)
To: qemu-devel; +Cc: peter.maydell, peter.crosthwaite
As the name suggests this lets you load a ROM/disk image that is
gzipped. It is uncompressed before storing it in guest memory.
Signed-off-by: Richard W.M. Jones <rjones@redhat.com>
---
hw/core/loader.c | 48 ++++++++++++++++++++++++++++++++++++++++++++++++
include/hw/loader.h | 1 +
2 files changed, 49 insertions(+)
diff --git a/hw/core/loader.c b/hw/core/loader.c
index 2bf6b8f..e773aab 100644
--- a/hw/core/loader.c
+++ b/hw/core/loader.c
@@ -577,6 +577,54 @@ int load_ramdisk(const char *filename, hwaddr addr, uint64_t max_sz)
return load_uboot_image(filename, NULL, &addr, NULL, IH_TYPE_RAMDISK);
}
+/* This simply prevents g_malloc in the function below from allocating
+ * a huge amount of memory, by placing a limit on the maximum
+ * uncompressed image size that load_image_gzipped will read.
+ */
+#define LOAD_IMAGE_MAX_GUNZIP_BYTES (256 << 20)
+
+/* Load a gzip-compressed kernel. */
+int load_image_gzipped(const char *filename, hwaddr addr, uint64_t max_sz)
+{
+ uint8_t *compressed_data = NULL;
+ uint8_t *data = NULL;
+ gsize len;
+ ssize_t bytes;
+ int ret = -1;
+
+ if (!g_file_get_contents(filename, (char **) &compressed_data, &len,
+ NULL)) {
+ goto out;
+ }
+
+ /* Is it a gzip-compressed file? */
+ if (len < 2 ||
+ compressed_data[0] != '\x1f' ||
+ compressed_data[1] != '\x8b') {
+ goto out;
+ }
+
+ if (max_sz > LOAD_IMAGE_MAX_GUNZIP_BYTES) {
+ max_sz = LOAD_IMAGE_MAX_GUNZIP_BYTES;
+ }
+
+ data = g_malloc(max_sz);
+ bytes = gunzip(data, max_sz, compressed_data, len);
+ if (bytes < 0) {
+ fprintf(stderr, "%s: unable to decompress gzipped kernel file\n",
+ filename);
+ goto out;
+ }
+
+ rom_add_blob_fixed(filename, data, bytes, addr);
+ ret = bytes;
+
+ out:
+ g_free(compressed_data);
+ g_free(data);
+ return ret;
+}
+
/*
* Functions for reboot-persistent memory regions.
* - used for vga bios and option roms.
diff --git a/include/hw/loader.h b/include/hw/loader.h
index 796cbf9..00c9117 100644
--- a/include/hw/loader.h
+++ b/include/hw/loader.h
@@ -15,6 +15,7 @@ int get_image_size(const char *filename);
int load_image(const char *filename, uint8_t *addr); /* deprecated */
int load_image_targphys(const char *filename, hwaddr,
uint64_t max_sz);
+int load_image_gzipped(const char *filename, hwaddr addr, uint64_t max_sz);
#define ELF_LOAD_FAILED -1
#define ELF_LOAD_NOT_ELF -2
--
2.0.4
^ permalink raw reply related [flat|nested] 7+ messages in thread
* [Qemu-devel] [PATCH v5 2/2] aarch64: Allow -kernel option to take a gzip-compressed kernel.
2014-08-04 11:47 [Qemu-devel] [PATCH v5 0/2] aarch64: Allow -kernel option to take a gzip-compressed kernel Richard W.M. Jones
2014-08-04 11:47 ` [Qemu-devel] [PATCH v5 1/2] loader: Add load_image_gzipped function Richard W.M. Jones
@ 2014-08-04 11:47 ` Richard W.M. Jones
2014-08-05 10:00 ` Alex Bennée
1 sibling, 1 reply; 7+ messages in thread
From: Richard W.M. Jones @ 2014-08-04 11:47 UTC (permalink / raw)
To: qemu-devel; +Cc: peter.maydell, peter.crosthwaite
On aarch64 it is the bootloader's job to uncompress the kernel. UEFI
and u-boot bootloaders do this automatically when the kernel is
gzip-compressed.
However the qemu -kernel option does not do this. The following
command does not work:
qemu-system-aarch64 [...] -kernel /boot/vmlinuz
because it tries to execute the gzip-compressed data.
This commit lets gzip-compressed kernels be uncompressed
transparently.
Currently this is only done when emulating aarch64.
Signed-off-by: Richard W.M. Jones <rjones@redhat.com>
---
hw/arm/boot.c | 9 +++++++++
1 file changed, 9 insertions(+)
diff --git a/hw/arm/boot.c b/hw/arm/boot.c
index 3d1f4a2..1d541db 100644
--- a/hw/arm/boot.c
+++ b/hw/arm/boot.c
@@ -444,6 +444,7 @@ static void do_cpu_reset(void *opaque)
void arm_load_kernel(ARMCPU *cpu, struct arm_boot_info *info)
{
CPUState *cs = CPU(cpu);
+ int allow_compressed_kernels = 0;
int kernel_size;
int initrd_size;
int is_linux = 0;
@@ -465,6 +466,7 @@ void arm_load_kernel(ARMCPU *cpu, struct arm_boot_info *info)
primary_loader = bootloader_aarch64;
kernel_load_offset = KERNEL64_LOAD_ADDR;
elf_machine = EM_AARCH64;
+ allow_compressed_kernels = 1;
} else {
primary_loader = bootloader;
kernel_load_offset = KERNEL_LOAD_ADDR;
@@ -510,6 +512,13 @@ void arm_load_kernel(ARMCPU *cpu, struct arm_boot_info *info)
kernel_size = load_uimage(info->kernel_filename, &entry, NULL,
&is_linux);
}
+ /* On aarch64, it's the bootloader's job to uncompress the kernel. */
+ if (allow_compressed_kernels && kernel_size < 0) {
+ entry = info->loader_start + kernel_load_offset;
+ kernel_size = load_image_gzipped(info->kernel_filename, entry,
+ info->ram_size - kernel_load_offset);
+ is_linux = 1;
+ }
if (kernel_size < 0) {
entry = info->loader_start + kernel_load_offset;
kernel_size = load_image_targphys(info->kernel_filename, entry,
--
2.0.4
^ permalink raw reply related [flat|nested] 7+ messages in thread
* Re: [Qemu-devel] [PATCH v5 1/2] loader: Add load_image_gzipped function.
2014-08-04 11:47 ` [Qemu-devel] [PATCH v5 1/2] loader: Add load_image_gzipped function Richard W.M. Jones
@ 2014-08-05 9:52 ` Alex Bennée
2014-08-05 9:57 ` Alex Bennée
1 sibling, 0 replies; 7+ messages in thread
From: Alex Bennée @ 2014-08-05 9:52 UTC (permalink / raw)
To: Richard W.M. Jones; +Cc: peter.maydell, peter.crosthwaite, qemu-devel
Richard W.M. Jones writes:
> As the name suggests this lets you load a ROM/disk image that is
> gzipped. It is uncompressed before storing it in guest memory.
>
<snip>
> +
> + /* Is it a gzip-compressed file? */
> + if (len < 2 ||
> + compressed_data[0] != '\x1f' ||
> + compressed_data[1] != '\x8b') {
> + goto out;
> + }
I was looking to see if the zlib library provided the magic numbers or a
verification routine here but I couldn't find it.
> +
> + if (max_sz > LOAD_IMAGE_MAX_GUNZIP_BYTES) {
> + max_sz = LOAD_IMAGE_MAX_GUNZIP_BYTES;
> + }
> +
> + data = g_malloc(max_sz);
> + bytes = gunzip(data, max_sz, compressed_data, len);
> + if (bytes < 0) {
> + fprintf(stderr, "%s: unable to decompress gzipped kernel file\n",
> + filename);
> + goto out;
> + }
> +
> + rom_add_blob_fixed(filename, data, bytes, addr);
> + ret = bytes;
> +
> + out:
> + g_free(compressed_data);
> + g_free(data);
> + return ret;
> +}
> +
> /*
> * Functions for reboot-persistent memory regions.
> * - used for vga bios and option roms.
> diff --git a/include/hw/loader.h b/include/hw/loader.h
> index 796cbf9..00c9117 100644
> --- a/include/hw/loader.h
> +++ b/include/hw/loader.h
> @@ -15,6 +15,7 @@ int get_image_size(const char *filename);
> int load_image(const char *filename, uint8_t *addr); /* deprecated */
> int load_image_targphys(const char *filename, hwaddr,
> uint64_t max_sz);
> +int load_image_gzipped(const char *filename, hwaddr addr, uint64_t max_sz);
>
> #define ELF_LOAD_FAILED -1
> #define ELF_LOAD_NOT_ELF -2
Reviewed-by: Alex Bennée <alex.bennee@linaro.org>
--
Alex Bennée
^ permalink raw reply [flat|nested] 7+ messages in thread
* Re: [Qemu-devel] [PATCH v5 1/2] loader: Add load_image_gzipped function.
2014-08-04 11:47 ` [Qemu-devel] [PATCH v5 1/2] loader: Add load_image_gzipped function Richard W.M. Jones
2014-08-05 9:52 ` Alex Bennée
@ 2014-08-05 9:57 ` Alex Bennée
2014-08-05 10:01 ` Richard W.M. Jones
1 sibling, 1 reply; 7+ messages in thread
From: Alex Bennée @ 2014-08-05 9:57 UTC (permalink / raw)
To: Richard W.M. Jones; +Cc: peter.maydell, peter.crosthwaite, qemu-devel
Richard W.M. Jones writes:
> As the name suggests this lets you load a ROM/disk image that is
> gzipped. It is uncompressed before storing it in guest memory.
>
> Signed-off-by: Richard W.M. Jones <rjones@redhat.com>
<snip>
> + /* Is it a gzip-compressed file? */
> + if (len < 2 ||
> + compressed_data[0] != '\x1f' ||
> + compressed_data[1] != '\x8b') {
> + goto out;
> + }
<snip>
Hmm serves me right for not compiling this first. I had to explicit
literals to get this to compile:
Modified hw/core/loader.c
diff --git a/hw/core/loader.c b/hw/core/loader.c
index e773aab..83136e8 100644
--- a/hw/core/loader.c
+++ b/hw/core/loader.c
@@ -599,8 +599,8 @@ int load_image_gzipped(const char *filename, hwaddr addr, uint64_t max_sz)
/* Is it a gzip-compressed file? */
if (len < 2 ||
- compressed_data[0] != '\x1f' ||
- compressed_data[1] != '\x8b') {
+ compressed_data[0] != 0x1f ||
+ compressed_data[1] != 0x8b ) {
goto out;
}
Otherwise I get:
hw/core/loader.c: In function ‘load_image_gzipped’:
hw/core/loader.c:603:9: error: comparison is always true due to limited range of data type [-Werror=type-limits]
compressed_data[1] != '\x8b') {
--
Alex Bennée
^ permalink raw reply related [flat|nested] 7+ messages in thread
* Re: [Qemu-devel] [PATCH v5 2/2] aarch64: Allow -kernel option to take a gzip-compressed kernel.
2014-08-04 11:47 ` [Qemu-devel] [PATCH v5 2/2] aarch64: Allow -kernel option to take a gzip-compressed kernel Richard W.M. Jones
@ 2014-08-05 10:00 ` Alex Bennée
0 siblings, 0 replies; 7+ messages in thread
From: Alex Bennée @ 2014-08-05 10:00 UTC (permalink / raw)
To: Richard W.M. Jones; +Cc: peter.maydell, peter.crosthwaite, qemu-devel
Richard W.M. Jones writes:
> On aarch64 it is the bootloader's job to uncompress the kernel. UEFI
> and u-boot bootloaders do this automatically when the kernel is
> gzip-compressed.
>
> However the qemu -kernel option does not do this. The following
> command does not work:
>
> qemu-system-aarch64 [...] -kernel /boot/vmlinuz
>
> because it tries to execute the gzip-compressed data.
>
> This commit lets gzip-compressed kernels be uncompressed
> transparently.
>
> Currently this is only done when emulating aarch64.
>
> Signed-off-by: Richard W.M. Jones <rjones@redhat.com>
> ---
> hw/arm/boot.c | 9 +++++++++
> 1 file changed, 9 insertions(+)
>
> diff --git a/hw/arm/boot.c b/hw/arm/boot.c
> index 3d1f4a2..1d541db 100644
> --- a/hw/arm/boot.c
> +++ b/hw/arm/boot.c
> @@ -444,6 +444,7 @@ static void do_cpu_reset(void *opaque)
> void arm_load_kernel(ARMCPU *cpu, struct arm_boot_info *info)
> {
> CPUState *cs = CPU(cpu);
> + int allow_compressed_kernels = 0;
> int kernel_size;
> int initrd_size;
> int is_linux = 0;
> @@ -465,6 +466,7 @@ void arm_load_kernel(ARMCPU *cpu, struct arm_boot_info *info)
> primary_loader = bootloader_aarch64;
> kernel_load_offset = KERNEL64_LOAD_ADDR;
> elf_machine = EM_AARCH64;
> + allow_compressed_kernels = 1;
> } else {
> primary_loader = bootloader;
> kernel_load_offset = KERNEL_LOAD_ADDR;
> @@ -510,6 +512,13 @@ void arm_load_kernel(ARMCPU *cpu, struct arm_boot_info *info)
> kernel_size = load_uimage(info->kernel_filename, &entry, NULL,
> &is_linux);
> }
> + /* On aarch64, it's the bootloader's job to uncompress the kernel. */
> + if (allow_compressed_kernels && kernel_size < 0) {
> + entry = info->loader_start + kernel_load_offset;
> + kernel_size = load_image_gzipped(info->kernel_filename, entry,
> + info->ram_size - kernel_load_offset);
> + is_linux = 1;
> + }
> if (kernel_size < 0) {
> entry = info->loader_start + kernel_load_offset;
> kernel_size = load_image_targphys(info->kernel_filename, entry,
Reviewed-by: Alex Bennée <alex.bennee@linaro.org>
--
Alex Bennée
^ permalink raw reply [flat|nested] 7+ messages in thread
* Re: [Qemu-devel] [PATCH v5 1/2] loader: Add load_image_gzipped function.
2014-08-05 9:57 ` Alex Bennée
@ 2014-08-05 10:01 ` Richard W.M. Jones
0 siblings, 0 replies; 7+ messages in thread
From: Richard W.M. Jones @ 2014-08-05 10:01 UTC (permalink / raw)
To: Alex Bennée; +Cc: peter.maydell, peter.crosthwaite, qemu-devel
On Tue, Aug 05, 2014 at 10:57:26AM +0100, Alex Bennée wrote:
>
> Richard W.M. Jones writes:
>
> > As the name suggests this lets you load a ROM/disk image that is
> > gzipped. It is uncompressed before storing it in guest memory.
> >
> > Signed-off-by: Richard W.M. Jones <rjones@redhat.com>
> <snip>
> > + /* Is it a gzip-compressed file? */
> > + if (len < 2 ||
> > + compressed_data[0] != '\x1f' ||
> > + compressed_data[1] != '\x8b') {
> > + goto out;
> > + }
> <snip>
>
> Hmm serves me right for not compiling this first. I had to explicit
> literals to get this to compile:
>
> Modified hw/core/loader.c
> diff --git a/hw/core/loader.c b/hw/core/loader.c
> index e773aab..83136e8 100644
> --- a/hw/core/loader.c
> +++ b/hw/core/loader.c
> @@ -599,8 +599,8 @@ int load_image_gzipped(const char *filename, hwaddr addr, uint64_t max_sz)
>
> /* Is it a gzip-compressed file? */
> if (len < 2 ||
> - compressed_data[0] != '\x1f' ||
> - compressed_data[1] != '\x8b') {
> + compressed_data[0] != 0x1f ||
> + compressed_data[1] != 0x8b ) {
> goto out;
> }
>
> Otherwise I get:
> hw/core/loader.c: In function ‘load_image_gzipped’:
> hw/core/loader.c:603:9: error: comparison is always true due to limited range of data type [-Werror=type-limits]
> compressed_data[1] != '\x8b') {
This is probably because I only compiled and tested this on aarch64
where char == unsigned char (not signed char).
I'll fix this in v6, thanks.
Rich.
--
Richard Jones, Virtualization Group, Red Hat http://people.redhat.com/~rjones
Read my programming and virtualization blog: http://rwmj.wordpress.com
virt-top is 'top' for virtual machines. Tiny program with many
powerful monitoring features, net stats, disk stats, logging, etc.
http://people.redhat.com/~rjones/virt-top
^ permalink raw reply [flat|nested] 7+ messages in thread
end of thread, other threads:[~2014-08-05 10:02 UTC | newest]
Thread overview: 7+ messages (download: mbox.gz / follow: Atom feed)
-- links below jump to the message on this page --
2014-08-04 11:47 [Qemu-devel] [PATCH v5 0/2] aarch64: Allow -kernel option to take a gzip-compressed kernel Richard W.M. Jones
2014-08-04 11:47 ` [Qemu-devel] [PATCH v5 1/2] loader: Add load_image_gzipped function Richard W.M. Jones
2014-08-05 9:52 ` Alex Bennée
2014-08-05 9:57 ` Alex Bennée
2014-08-05 10:01 ` Richard W.M. Jones
2014-08-04 11:47 ` [Qemu-devel] [PATCH v5 2/2] aarch64: Allow -kernel option to take a gzip-compressed kernel Richard W.M. Jones
2014-08-05 10:00 ` Alex Bennée
This is an external index of several public inboxes,
see mirroring instructions on how to clone and mirror
all data and code used by this external index.