diff options
| author | Martin Schwidefsky <schwidefsky@de.ibm.com> | 2015-07-06 17:58:19 +0200 |
|---|---|---|
| committer | Ben Hutchings <ben@decadent.org.uk> | 2015-08-12 16:33:20 +0200 |
| commit | 436bd506eaab4da2edf986306135ce3964eecf36 (patch) | |
| tree | ee9df6ef9db27f8493455409c326aa4a66c05ffe /arch | |
| parent | a62b33eed7aba186f0d8ffad97b732335db414c8 (diff) | |
| download | kernel_samsung_smdk4412-436bd506eaab4da2edf986306135ce3964eecf36.zip kernel_samsung_smdk4412-436bd506eaab4da2edf986306135ce3964eecf36.tar.gz kernel_samsung_smdk4412-436bd506eaab4da2edf986306135ce3964eecf36.tar.bz2 | |
s390/sclp: clear upper register halves in _sclp_print_early
commit f9c87a6f46d508eae0d9ae640be98d50f237f827 upstream.
If the kernel is compiled with gcc 5.1 and the XZ compression option
the decompress_kernel function calls _sclp_print_early in 64-bit mode
while the content of the upper register half of %r6 is non-zero.
This causes a specification exception on the servc instruction in
_sclp_servc.
The _sclp_print_early function saves and restores the upper registers
halves but it fails to clear them for the 31-bit code of the mini sclp
driver.
Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
Signed-off-by: Ben Hutchings <ben@decadent.org.uk>
Diffstat (limited to 'arch')
| -rw-r--r-- | arch/s390/kernel/sclp.S | 4 |
1 files changed, 4 insertions, 0 deletions
diff --git a/arch/s390/kernel/sclp.S b/arch/s390/kernel/sclp.S index 95792d8..51ca1c3 100644 --- a/arch/s390/kernel/sclp.S +++ b/arch/s390/kernel/sclp.S @@ -270,6 +270,8 @@ ENTRY(_sclp_print_early) jno .Lesa2 ahi %r15,-80 stmh %r6,%r15,96(%r15) # store upper register halves + basr %r13,0 + lmh %r0,%r15,.Lzeroes-.(%r13) # clear upper register halves .Lesa2: #endif lr %r10,%r2 # save string pointer @@ -293,6 +295,8 @@ ENTRY(_sclp_print_early) #endif lm %r6,%r15,120(%r15) # restore registers br %r14 +.Lzeroes: + .fill 64,4,0 .LwritedataS4: .long 0x00760005 # SCLP command for write data |