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| author | Philipp Rudo <prudo@linux.ibm.com> | 2018-06-27 13:03:43 +0300 |
|---|---|---|
| committer | Martin Schwidefsky <schwidefsky@de.ibm.com> | 2018-07-06 09:47:51 +0300 |
| commit | 287d6070acbb2529e24462faffca46663885dddc (patch) | |
| tree | 25a34c095e4d1983926043f92bf4ca5fb86e3141 /arch/s390/purgatory/head.S | |
| parent | c315e69308c739a43c4ebc539bedbc1ac8d79854 (diff) | |
| download | linux-287d6070acbb2529e24462faffca46663885dddc.tar.xz | |
s390/purgatory: Remove duplicate variable definitions
Currently there are some variables in the purgatory (e.g. kernel_entry)
which are defined twice, once in assembler- and once in c-code. The reason
for this is that these variables are set during purgatory load, where
sanity checks on the corresponding Elf_Sym's are made, while they are used
in assembler-code. Thus adding a second definition in c-code is a handy
workaround to guarantee correct Elf_Sym's are created.
When the purgatory is compiled with -fcommon (default for gcc on s390) this
is no problem because both symbols are merged by the linker. However this
is not required by ISO C and when the purgatory is built with -fno-common
the linker fails with errors like
arch/s390/purgatory/purgatory.o:(.bss+0x18): multiple definition of `kernel_entry'
arch/s390/purgatory/head.o:/.../arch/s390/purgatory/head.S:230: first defined here
Thus remove the duplicate definitions and add the required size and type
information to the assembler definition. Also add -fno-common to the
command line options to prevent similar hacks in the future.
Signed-off-by: Philipp Rudo <prudo@linux.ibm.com>
Acked-by: Heiko Carstens <heiko.carstens@de.ibm.com>
Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
Diffstat (limited to 'arch/s390/purgatory/head.S')
| -rw-r--r-- | arch/s390/purgatory/head.S | 45 |
1 files changed, 19 insertions, 26 deletions
diff --git a/arch/s390/purgatory/head.S b/arch/s390/purgatory/head.S index 660c96a05a9b..2e3707b12edd 100644 --- a/arch/s390/purgatory/head.S +++ b/arch/s390/purgatory/head.S @@ -243,33 +243,26 @@ gprregs: .quad 0 .endr -purgatory_sha256_digest: - .global purgatory_sha256_digest - .rept 32 /* SHA256_DIGEST_SIZE */ - .byte 0 - .endr - -purgatory_sha_regions: - .global purgatory_sha_regions - .rept 16 * __KEXEC_SHA_REGION_SIZE /* KEXEC_SEGMENTS_MAX */ - .byte 0 - .endr - -kernel_entry: - .global kernel_entry - .quad 0 - -kernel_type: - .global kernel_type - .quad 0 - -crash_start: - .global crash_start - .quad 0 +/* Macro to define a global variable with name and size (in bytes) to be + * shared with C code. + * + * Add the .size and .type attribute to satisfy checks on the Elf_Sym during + * purgatory load. + */ +.macro GLOBAL_VARIABLE name,size +\name: + .global \name + .size \name,\size + .type \name,object + .skip \size,0 +.endm -crash_size: - .global crash_size - .quad 0 +GLOBAL_VARIABLE purgatory_sha256_digest,32 +GLOBAL_VARIABLE purgatory_sha_regions,16*__KEXEC_SHA_REGION_SIZE +GLOBAL_VARIABLE kernel_entry,8 +GLOBAL_VARIABLE kernel_type,8 +GLOBAL_VARIABLE crash_start,8 +GLOBAL_VARIABLE crash_size,8 .align PAGE_SIZE stack: |