kernel/linux.git/arch/arm/boot/compressed, branch v5.15.208

ARM: decompressor: Include .data.rel.ro.local

2022-10-26T10:35:31+00:00

[ Upstream commit 1b64daf413acd86c2c13f5443f6b4ef3690c8061 ] The .data.rel.ro.local section has the same semantics as .data.rel.ro here, so include it in the .rodata section of the decompressor. Additionally since the .printk_index section isn't usable outside of the core kernel, discard it in the decompressor. Avoids these warnings: arm-linux-gnueabi-ld: warning: orphan section `.data.rel.ro.local' from `arch/arm/boot/compressed/fdt_rw.o' being placed in section `.data.rel.ro.local' arm-linux-gnueabi-ld: warning: orphan section `.printk_index' from `arch/arm/boot/compressed/fdt_rw.o' being placed in section `.printk_index' Reported-by: kernel test robot Link: https://lore.kernel.org/linux-mm/202209080545.qMIVj7YM-lkp@intel.com Cc: Russell King Cc: linux-arm-kernel@lists.infradead.org Signed-off-by: Kees Cook Signed-off-by: Sasha Levin

ARM: 9159/1: decompressor: Avoid UNPREDICTABLE NOP encoding

2022-01-27T10:03:40+00:00

[ Upstream commit a92882a4d270fbcc021ee6848de5e48b7f0d27f3 ] In the decompressor's head.S we need to start with an instruction that is some kind of NOP, but also mimics as the PE/COFF header, when the kernel is linked as an UEFI application. The clever solution here is "tstne r0, #0x4d000", which in the worst case just clobbers the condition flags, and bears the magic "MZ" signature in the lowest 16 bits. However the encoding used (0x13105a4d) is actually not valid, since bits [15:12] are supposed to be 0 (written as "(0)" in the ARM ARM). Violating this is UNPREDICTABLE, and *can* trigger an UNDEFINED exception. Common Cortex cores seem to ignore those bits, but QEMU chooses to trap, so the code goes fishing because of a missing exception handler at this point. We are just saved by the fact that commonly (with -kernel or when running from U-Boot) the "Z" bit is set, so the instruction is never executed. See [0] for more details. To make things more robust and avoid UNPREDICTABLE behaviour in the kernel code, lets replace this with a "two-instruction NOP": The first instruction is an exclusive OR, the effect of which the second instruction reverts. This does not leave any trace, neither in a register nor in the condition flags. Also it's a perfectly valid encoding. Kudos to Peter Maydell for coming up with this gem. [0] https://lore.kernel.org/qemu-devel/YTPIdbUCmwagL5%2FD@os.inf.tu-dresden.de/T/ Link: https://lore.kernel.org/linux-arm-kernel/20210908162617.104962-1-andre.przywara@arm.com/T/ Fixes: 81a0bc39ea19 ("ARM: add UEFI stub support") Signed-off-by: Andre Przywara Reported-by: Adam Lackorzynski Suggested-by: Peter Maydell Reviewed-by: Ard Biesheuvel Reviewed-by: Linus Walleij Signed-off-by: Russell King (Oracle) Signed-off-by: Sasha Levin

ARM: 9134/1: remove duplicate memcpy() definition

2021-10-19T09:37:36+00:00

Both the decompressor code and the kasan logic try to override the memcpy() and memmove() definitions, which leading to a clash in a KASAN-enabled kernel with XZ decompression: arch/arm/boot/compressed/decompress.c:50:9: error: 'memmove' macro redefined [-Werror,-Wmacro-redefined] #define memmove memmove ^ arch/arm/include/asm/string.h:59:9: note: previous definition is here #define memmove(dst, src, len) __memmove(dst, src, len) ^ arch/arm/boot/compressed/decompress.c:51:9: error: 'memcpy' macro redefined [-Werror,-Wmacro-redefined] #define memcpy memcpy ^ arch/arm/include/asm/string.h:58:9: note: previous definition is here #define memcpy(dst, src, len) __memcpy(dst, src, len) ^ Here we want the set of functions from the decompressor, so undefine the other macros before the override. Link: https://lore.kernel.org/linux-arm-kernel/CACRpkdZYJogU_SN3H9oeVq=zJkRgRT1gDz3xp59gdqWXxw-B=w@mail.gmail.com/ Link: https://lore.kernel.org/lkml/202105091112.F5rmd4By-lkp@intel.com/ Fixes: d6d51a96c7d6 ("ARM: 9014/2: Replace string mem* functions for KASan") Fixes: a7f464f3db93 ("ARM: 7001/2: Wire up support for the XZ decompressor") Reported-by: kernel test robot Reviewed-by: Linus Walleij Signed-off-by: Arnd Bergmann Signed-off-by: Russell King (Oracle)

ARM: 9105/1: atags_to_fdt: don't warn about stack size

2021-08-10T11:17:42+00:00

The merge_fdt_bootargs() function by definition consumes more than 1024 bytes of stack because it has a 1024 byte command line on the stack, meaning that we always get a warning when building this file: arch/arm/boot/compressed/atags_to_fdt.c: In function 'merge_fdt_bootargs': arch/arm/boot/compressed/atags_to_fdt.c:98:1: warning: the frame size of 1032 bytes is larger than 1024 bytes [-Wframe-larger-than=] However, as this is the decompressor and we know that it has a very shallow call chain, and we do not actually risk overflowing the kernel stack at runtime here. This just shuts up the warning by disabling the warning flag for this file. Tested on Nexus 7 2012 builds. Acked-by: Nicolas Pitre Signed-off-by: David Heidelberg Signed-off-by: Arnd Bergmann Cc: Signed-off-by: Russell King (Oracle)

ARM: 9083/1: uncompress: atags_to_fdt: Spelling s/REturn/Return/

2021-06-07T11:56:21+00:00

Fix a capitalization typo. Signed-off-by: Geert Uytterhoeven Signed-off-by: Russell King

ARM: 9076/1: boot: remove redundant piggy_data from clean-files

2021-06-07T11:56:20+00:00

Kbuild cleans up files listed in 'targets'. 'piggy_data' is already added to 'targets' a few lines above. Adding it to 'clean-files' is redundant. Signed-off-by: Masahiro Yamada Signed-off-by: Russell King

Merge tag 'kbuild-v5.13-2' of git://git.kernel.org/pub/scm/linux/kernel/git/masahiroy/linux-kbuild

2021-05-08T17:00:11+00:00

Pull more Kbuild updates from Masahiro Yamada: - Convert sh and sparc to use generic shell scripts to generate the syscall headers - refactor .gitignore files - Update kernel/config_data.gz only when the content of the .config is really changed, which avoids the unneeded re-link of vmlinux - move "remove stale files" workarounds to scripts/remove-stale-files - suppress unused-but-set-variable warnings by default for Clang as well - fix locale setting LANG=C to LC_ALL=C - improve 'make distclean' - always keep intermediate objects from scripts/link-vmlinux.sh - move IF_ENABLED out of to make it self-contained - misc cleanups * tag 'kbuild-v5.13-2' of git://git.kernel.org/pub/scm/linux/kernel/git/masahiroy/linux-kbuild: (25 commits) linux/kconfig.h: replace IF_ENABLED() with PTR_IF() in kbuild: Don't remove link-vmlinux temporary files on exit/signal kbuild: remove the unneeded comments for external module builds kbuild: make distclean remove tag files in sub-directories kbuild: make distclean work against $(objtree) instead of $(srctree) kbuild: refactor modname-multi by using suffix-search kbuild: refactor fdtoverlay rule kbuild: parameterize the .o part of suffix-search arch: use cross_compiling to check whether it is a cross build or not kbuild: remove ARCH=sh64 support from top Makefile .gitignore: prefix local generated files with a slash kbuild: replace LANG=C with LC_ALL=C Makefile: Move -Wno-unused-but-set-variable out of GCC only block kbuild: add a script to remove stale generated files kbuild: update config_data.gz only when the content of .config is changed .gitignore: ignore only top-level modules.builtin .gitignore: move tags and TAGS close to other tag files kernel/.gitgnore: remove stale timeconst.h and hz.bc usr/include: refactor .gitignore genksyms: fix stale comment ...

kbuild: add a script to remove stale generated files

2021-05-01T15:43:35+00:00

We maintain .gitignore and Makefiles so build artifacts are properly ignored by Git, and cleaned up by 'make clean'. However, the code is always changing; generated files are often moved to another directory, or removed when they become unnecessary. Such garbage files tend to be left over in the source tree because people usually git-pull without cleaning the tree. This is not only the noise for 'git status', but also a build issue in some cases. One solution is to remove a stale file like commit 223c24a7dba9 ("kbuild: Automatically remove stale file") did. Such workaround should be removed after a while, but we forget about that if we scatter the workaround code in random places. So, this commit adds a new script to collect cleanings of stale files. As a start point, move the code in arch/arm/boot/compressed/Makefile into this script. Signed-off-by: Masahiro Yamada

ARM: 9056/1: decompressor: fix BSS size calculation for LLVM ld.lld

2021-03-09T10:25:17+00:00

The LLVM ld.lld linker uses a different symbol type for __bss_start, resulting in the calculation of KBSS_SZ to be thrown off. Up until now, this has gone unnoticed as it only affects the appended DTB case, but pending changes for ARM in the way the decompressed kernel is cleaned from the caches has uncovered this problem. On a ld.lld build: $ nm vmlinux |grep bss_ c1c22034 D __bss_start c1c86e98 B __bss_stop resulting in $ readelf -s arch/arm/boot/compressed/vmlinux | grep bss_size 433: c1c86e98 0 NOTYPE GLOBAL DEFAULT ABS _kernel_bss_size which is obviously incorrect, and may cause the cache clean to access unmapped memory, or cause the size calculation to wrap, resulting in no cache clean to be performed at all. Fix this by updating the sed regex to take D type symbols into account. Link: https://lore.kernel.org/linux-arm-kernel/6c65bcef-d4e7-25fa-43cf-2c435bb61bb9@collabora.com/ Link: https://lore.kernel.org/linux-arm-kernel/20210205085220.31232-1-ardb@kernel.org/ Cc: # v4.19+ Reviewed-by: Nick Desaulniers Tested-by: Nick Desaulniers Reported-by: Guillaume Tucker Reported-by: "kernelci.org bot" Signed-off-by: Ard Biesheuvel Signed-off-by: Russell King

Merge tag 'for-linus' of git://git.armlinux.org.uk/~rmk/linux-arm

2021-02-22T22:27:07+00:00

Pull ARM updates from Russell King: - Generalise byte swapping assembly - Update debug addresses for STI - Validate start of physical memory with DTB - Do not clear SCTLR.nTLSMD in decompressor - amba/locomo/sa1111 devices remove method return type is void - address markers for KASAN in page table dump * tag 'for-linus' of git://git.armlinux.org.uk/~rmk/linux-arm: ARM: 9065/1: OABI compat: fix build when EPOLL is not enabled ARM: 9055/1: mailbox: arm_mhuv2: make remove callback return void amba: Make use of bus_type functions amba: Make the remove callback return void vfio: platform: simplify device removal amba: reorder functions amba: Fix resource leak for drivers without .remove ARM: 9054/1: arch/arm/mm/mmu.c: Remove duplicate header ARM: 9053/1: arm/mm/ptdump:Add address markers for KASAN regions ARM: 9051/1: vdso: remove unneded extra-y addition ARM: 9050/1: Kconfig: Select ARCH_HAVE_NMI_SAFE_CMPXCHG where possible ARM: 9049/1: locomo: make locomo bus's remove callback return void ARM: 9048/1: sa1111: make sa1111 bus's remove callback return void ARM: 9047/1: smp: remove unused variable ARM: 9046/1: decompressor: Do not clear SCTLR.nTLSMD for ARMv7+ cores ARM: 9045/1: uncompress: Validate start of physical memory against passed DTB ARM: 9042/1: debug: no uncompress debugging while semihosting ARM: 9041/1: sti LL_UART: add STiH418 SBC UART0 support ARM: 9040/1: use DEBUG_UART_PHYS and DEBUG_UART_VIRT for sti LL_UART ARM: 9039/1: assembler: generalize byte swapping macro into rev_l