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 <lkp@intel.com>
Reviewed-by: Linus Walleij <linus.walleij@linaro.org>
Signed-off-by: Arnd Bergmann <arnd@arndb.de>
Signed-off-by: Russell King (Oracle) <rmk+kernel@armlinux.org.uk>
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 <nico@fluxnic.net> Signed-off-by: David Heidelberg <david@ixit.cz> Signed-off-by: Arnd Bergmann <arnd@arndb.de> Cc: <stable@vger.kernel.org> Signed-off-by: Russell King (Oracle) <rmk+kernel@armlinux.org.uk>
Fix a capitalization typo. Signed-off-by: Geert Uytterhoeven <geert+renesas@glider.be> Signed-off-by: Russell King <rmk+kernel@armlinux.org.uk>
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 <masahiroy@kernel.org> Signed-off-by: Russell King <rmk+kernel@armlinux.org.uk>
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 <linux/kconfig.h> 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 <linux/kernel.h> 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 ...
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 <linux/version.h> 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 <masahiroy@kernel.org>
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: <stable@vger.kernel.org> # v4.19+ Reviewed-by: Nick Desaulniers <ndesaulniers@google.com> Tested-by: Nick Desaulniers <ndesaulniers@google.com> Reported-by: Guillaume Tucker <guillaume.tucker@collabora.com> Reported-by: "kernelci.org bot" <bot@kernelci.org> Signed-off-by: Ard Biesheuvel <ardb@kernel.org> Signed-off-by: Russell King <rmk+kernel@armlinux.org.uk>
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
It was observed that decompressor running on hardware implementing ARM v8.2
Load/Store Multiple Atomicity and Ordering Control (LSMAOC), say, as guest,
would stuck just after:
Uncompressing Linux... done, booting the kernel.
The reason is that it clears nTLSMD bit when disabling caches:
nTLSMD, bit [3]
When ARMv8.2-LSMAOC is implemented:
No Trap Load Multiple and Store Multiple to
Device-nGRE/Device-nGnRE/Device-nGnRnE memory.
0b0 All memory accesses by A32 and T32 Load Multiple and Store
Multiple at EL1 or EL0 that are marked at stage 1 as
Device-nGRE/Device-nGnRE/Device-nGnRnE memory are trapped and
generate a stage 1 Alignment fault.
0b1 All memory accesses by A32 and T32 Load Multiple and Store
Multiple at EL1 or EL0 that are marked at stage 1 as
Device-nGRE/Device-nGnRE/Device-nGnRnE memory are not trapped.
This bit is permitted to be cached in a TLB.
This field resets to 1.
Otherwise:
Reserved, RES1
So as effect we start getting traps we are not quite ready for.
Looking into history it seems that mask used for SCTLR clear came from
the similar code for ARMv4, where bit[3] is the enable/disable bit for
the write buffer. That not applicable to ARMv7 and onwards, so retire
that bit from the masks.
Fixes: 7d09e85448dfa78e3e58186c934449aaf6d49b50 ("[ARM] 4393/2: ARMv7: Add uncompressing code for the new CPU Id format")
Signed-off-by: Vladimir Murzin <vladimir.murzin@arm.com>
Signed-off-by: Russell King <rmk+kernel@armlinux.org.uk>
Currently, the start address of physical memory is obtained by masking the program counter with a fixed mask of 0xf8000000. This mask value was chosen as a balance between the requirements of different platforms. However, this does require that the start address of physical memory is a multiple of 128 MiB, precluding booting Linux on platforms where this requirement is not fulfilled. Fix this limitation by validating the masked address against the memory information in the passed DTB. Only use the start address from DTB when masking would yield an out-of-range address, prefer the traditional method in all other cases. Note that this applies only to the explicitly passed DTB on modern systems, and not to a DTB appended to the kernel, or to ATAGS. The appended DTB may need to be augmented by information from ATAGS, which may need to rely on knowledge of the start address of physical memory itself. This allows to boot Linux on r7s9210/rza2mevb using the 64 MiB of SDRAM on the RZA2MEVB sub board, which is located at 0x0C000000 (CS3 space), i.e. not at a multiple of 128 MiB. Suggested-by: Nicolas Pitre <nico@fluxnic.net> Suggested-by: Ard Biesheuvel <ardb@kernel.org> Signed-off-by: Geert Uytterhoeven <geert+renesas@glider.be> Reviewed-by: Ard Biesheuvel <ardb@kernel.org> Acked-by: Nicolas Pitre <nico@fluxnic.net> Signed-off-by: Russell King <rmk+kernel@armlinux.org.uk>