6.12-stable patches

added patches:
	efi-zboot-limit-compression-options-to-gzip-and-zstd.patch
	series

diff --git a/queue-6.12/efi-zboot-limit-compression-options-to-gzip-and-zstd.patch b/queue-6.12/efi-zboot-limit-compression-options-to-gzip-and-zstd.patch
new file mode 100644 (file)
index 0000000..cf52b4b
--- /dev/null
+++ b/queue-6.12/efi-zboot-limit-compression-options-to-gzip-and-zstd.patch
@@ -0,0 +1,82 @@
+From 0b2c29fb68f8bf3e87a9d88404aa6fdd486223e5 Mon Sep 17 00:00:00 2001
+From: Ard Biesheuvel <ardb@kernel.org>
+Date: Fri, 6 Dec 2024 11:41:40 +0100
+Subject: efi/zboot: Limit compression options to GZIP and ZSTD
+
+From: Ard Biesheuvel <ardb@kernel.org>
+
+commit 0b2c29fb68f8bf3e87a9d88404aa6fdd486223e5 upstream.
+
+For historical reasons, the legacy decompressor code on various
+architectures supports 7 different compression types for the compressed
+kernel image.
+
+EFI zboot is not a compression library museum, and so the options can be
+limited to what is likely to be useful in practice:
+
+- GZIP is tried and tested, and is still one of the fastest at
+  decompression time, although the compression ratio is not very high;
+  moreover, Fedora is already shipping EFI zboot kernels for arm64 that
+  use GZIP, and QEMU implements direct support for it when booting a
+  kernel without firmware loaded;
+
+- ZSTD has a very high compression ratio (although not the highest), and
+  is almost as fast as GZIP at decompression time.
+
+Reducing the number of options makes it less of a hassle for other
+consumers of the EFI zboot format (such as QEMU today, and kexec in the
+future) to support it transparently without having to carry 7 different
+decompression libraries.
+
+Acked-by: Gerd Hoffmann <kraxel@redhat.com>
+Signed-off-by: Ard Biesheuvel <ardb@kernel.org>
+Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
+---
+ drivers/firmware/efi/Kconfig                |    4 ----
+ drivers/firmware/efi/libstub/Makefile.zboot |   18 ++++++------------
+ 2 files changed, 6 insertions(+), 16 deletions(-)
+
+--- a/drivers/firmware/efi/Kconfig
++++ b/drivers/firmware/efi/Kconfig
+@@ -76,10 +76,6 @@ config EFI_ZBOOT
+       bool "Enable the generic EFI decompressor"
+       depends on EFI_GENERIC_STUB && !ARM
+       select HAVE_KERNEL_GZIP
+-      select HAVE_KERNEL_LZ4
+-      select HAVE_KERNEL_LZMA
+-      select HAVE_KERNEL_LZO
+-      select HAVE_KERNEL_XZ
+       select HAVE_KERNEL_ZSTD
+       help
+         Create the bootable image as an EFI application that carries the
+--- a/drivers/firmware/efi/libstub/Makefile.zboot
++++ b/drivers/firmware/efi/libstub/Makefile.zboot
+@@ -12,22 +12,16 @@ quiet_cmd_copy_and_pad = PAD     $@
+ $(obj)/vmlinux.bin: $(obj)/$(EFI_ZBOOT_PAYLOAD) FORCE
+       $(call if_changed,copy_and_pad)
+ 
+-comp-type-$(CONFIG_KERNEL_GZIP)               := gzip
+-comp-type-$(CONFIG_KERNEL_LZ4)                := lz4
+-comp-type-$(CONFIG_KERNEL_LZMA)               := lzma
+-comp-type-$(CONFIG_KERNEL_LZO)                := lzo
+-comp-type-$(CONFIG_KERNEL_XZ)         := xzkern
+-comp-type-$(CONFIG_KERNEL_ZSTD)               := zstd22
+-
+ # in GZIP, the appended le32 carrying the uncompressed size is part of the
+ # format, but in other cases, we just append it at the end for convenience,
+ # causing the original tools to complain when checking image integrity.
+-# So disregard it when calculating the payload size in the zimage header.
+-zboot-method-y                         := $(comp-type-y)_with_size
+-zboot-size-len-y                       := 4
++comp-type-y                           := gzip
++zboot-method-y                                := gzip
++zboot-size-len-y                      := 0
+ 
+-zboot-method-$(CONFIG_KERNEL_GZIP)     := gzip
+-zboot-size-len-$(CONFIG_KERNEL_GZIP)   := 0
++comp-type-$(CONFIG_KERNEL_ZSTD)               := zstd
++zboot-method-$(CONFIG_KERNEL_ZSTD)    := zstd22_with_size
++zboot-size-len-$(CONFIG_KERNEL_ZSTD)  := 4
+ 
+ $(obj)/vmlinuz: $(obj)/vmlinux.bin FORCE
+       $(call if_changed,$(zboot-method-y))

diff --git a/queue-6.12/series b/queue-6.12/series
new file mode 100644 (file)
index 0000000..a2f6082
--- /dev/null
+++ b/queue-6.12/series
@@ -0,0 +1 @@
+efi-zboot-limit-compression-options-to-gzip-and-zstd.patch