Commit Graph

85 Commits

Author SHA1 Message Date
Vasily Gorbik
88731c8f36 s390/boot: fix zstd build for -march=z900
zstd decompression uses __builtin_clz() which fails back to __clzdi2()
when the kernel is built for older hardware like z900. This leads to
build failures like the following:
s390x-11.1.0-ld: /devel/src/kernel/arch/s390/boot/compressed/../../../../lib/zstd/bitstream.h:148: undefined reference to `__clzdi2'

Fix that by optionally including lib/clz_ctz.c into the decompressor.

Reported-by: kernel test robot <lkp@intel.com>
Fixes: 7b034d9c1b ("s390/boot: add zstd support")
Signed-off-by: Vasily Gorbik <gor@linux.ibm.com>
Link: https://lore.kernel.org/r/patch-1.thread-f0f589.git-f0f58936888f.your-ad-here.call-01627564869-ext-2765@work.hours
Signed-off-by: Heiko Carstens <hca@linux.ibm.com>
2021-07-30 17:08:22 +02:00
Dimitri John Ledkov
7b034d9c1b s390/boot: add zstd support
Enable ztsd support in s390/boot, to enable booting with zstd
compressed kernel when configured with CONFIG_KERNEL_ZSTD=y.

BOOT_HEAP_SIZE is defined to 0x30000 in this case. Actual decompressor
memory usage with allyesconfig is currently 0x26150.

BugLink: https://bugs.launchpad.net/bugs/1931725
Signed-off-by: Dimitri John Ledkov <dimitri.ledkov@canonical.com>
cc: Heiko Carstens <hca@linux.ibm.com>
cc: Vasily Gorbik <gor@linux.ibm.com>
cc: Christian Borntraeger <borntraeger@de.ibm.com>
cc: linux-s390@vger.kernel.org
Link: https://lore.kernel.org/r/20210615114150.325080-1-dimitri.ledkov@canonical.com
[gor: added BOOT_HEAP_SIZE for zstd]
Signed-off-by: Vasily Gorbik <gor@linux.ibm.com>
2021-06-18 16:41:22 +02:00
Vasily Gorbik
54f4521452 s390/decompressor: correct BOOT_HEAP_SIZE condition
Currently BOOT_HEAP_SIZE is always defined as 0x400000 due to
bogus condition. Use CONFIG_KERNEL_BZIP2 instead of
CONFIG_HAVE_KERNEL_BZIP2 to correct that.

BOOT_HEAP_SIZE of 0x10000 is still good enough for every decompressor
algorithm but bzip2. Actual decompressor memory usage with allyesconfig
is the following:
gzip  0xbc28
bzip2 0x379518
xz    0x7410
lzma  0x3e6c
lzo   0
lz4   0

Signed-off-by: Vasily Gorbik <gor@linux.ibm.com>
2021-06-18 16:41:22 +02:00
Rob Landley
113af8e6f4 s390/decompressor: replace use of perl with simple sed/tr
Use simple sed/tr instead of perl to generate decompressor symbols
file with the same result.

Signed-off-by: Rob Landley <rob@landley.net>
Signed-off-by: Vasily Gorbik <gor@linux.ibm.com>
[gor: changed commit message]
Link: https://lore.kernel.org/r/a48c51f8-5fe4-87e7-284e-c96e2381801a@landley.net
Signed-off-by: Vasily Gorbik <gor@linux.ibm.com>
2021-06-07 17:12:59 +02:00
Philipp Rudo
7a84ffc047 s390/boot: add build-id to decompressor
More and more functionality from the early boot phase gets carried over
to the decompressor. With this the complexity of the code and thus the
chance to introduce bugs increases. In order to be able to debug these
early boot bugs the distributions have to package the decompressors
vmlinux together with the other debuginfos. However for that the
distributions require the vmlinux to contain a build-id.

Per default the section containing the build-id is placed first in the
section table. So make sure to move it behind the .text section
otherwise the image would be unbootable.

Signed-off-by: Philipp Rudo <prudo@linux.ibm.com>
Signed-off-by: Heiko Carstens <hca@linux.ibm.com>
2020-12-09 21:02:07 +01:00
Vasily Gorbik
246218962e s390/decompressor: add symbols support
Information printed by print_pgm_check_info() is crucial for
debugging decompressor problems. Printing instruction addresses is
better than nothing, but turns further debugging into tedious job of
figuring out which function those addresses correspond to.

This change adds simplistic symbols resolution support. And adds %pS
format specifier support to decompressor_printk().

Decompressor symbols list is extracted and sorted with
nm -n -S:
...
0000000000010000 0000000000000014 T startup
0000000000010014 00000000000000b0 t startup_normal
0000000000010180 00000000000000b2 t startup_kdump
...

Then functions are filtered and contracted to a form:
"10000 14 startup\0""10014 b0 startup_normal\0""10180 b2 startup_kdump\0"
...
Which makes it trivial to find beginning of an entry and names are 0
terminated, so could be used as is. Symbols are binary-searched.

To get symbols list with final addresses and then get it into the
decompressor's image the same trick as for kallsyms is used.
Decompressor's vmlinux is linked twice.

Symbols are stored in .decompressor.syms section, current size is about
2kb.

Reviewed-by: Alexander Egorenkov <egorenar@linux.ibm.com>
Signed-off-by: Vasily Gorbik <gor@linux.ibm.com>
Signed-off-by: Heiko Carstens <hca@linux.ibm.com>
2020-11-20 19:19:11 +01:00
Vasily Gorbik
39f2899b98 s390/decompressor: fix build warning
Fixes the following warning with CONFIG_KERNEL_UNCOMPRESSED=y

arch/s390/boot/compressed/decompressor.h:6:46: warning: non-void function
does not return a value [-Wreturn-type]
static inline void *decompress_kernel(void) {}
                                             ^

Signed-off-by: Vasily Gorbik <gor@linux.ibm.com>
Signed-off-by: Heiko Carstens <hca@linux.ibm.com>
2020-11-09 11:20:59 +01:00
Alexander Egorenkov
980d5f9ab3 s390/boot: enable .bss section for compressed kernel
- Support static uninitialized variables in compressed kernel.
- Remove chkbss script
- Get rid of workarounds for not having .bss section

Signed-off-by: Alexander Egorenkov <egorenar@linux.ibm.com>
Reviewed-by: Vasily Gorbik <gor@linux.ibm.com>
Signed-off-by: Vasily Gorbik <gor@linux.ibm.com>
2020-09-16 14:08:47 +02:00
Masahiro Yamada
d198b34f38 .gitignore: add SPDX License Identifier
Add SPDX License Identifier to all .gitignore files.

Signed-off-by: Masahiro Yamada <masahiroy@kernel.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2020-03-25 11:50:48 +01:00
Mikhail Zaslonko
1b3e3faf29 s390/boot: rename HEAP_SIZE due to name collision
Change the conflicting macro name in preparation for zlib_inflate
hardware support.

Link: http://lkml.kernel.org/r/20200103223334.20669-3-zaslonko@linux.ibm.com
Signed-off-by: Mikhail Zaslonko <zaslonko@linux.ibm.com>
Reviewed-by: Christian Borntraeger <borntraeger@de.ibm.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2020-01-31 10:30:40 -08:00
Vasily Gorbik
80ef517b01 s390/startup: adjust _sdma and _edma to page boundaries
Move .dma.text section alignment out of section description, otherwise
zeros used to align the section are included in the section itself (and
section is not really aligned by itself).
$ objdump -h arch/s390/boot/compressed/vmlinux
  5 .dma.text     00001e38  000000000001b1c8  000000000001b1c8  0001c1c8  2**2
                  CONTENTS, ALLOC, LOAD, READONLY, CODE
  6 .dma.ex_table 00000018  000000000001d000  000000000001d000  0001e000  2**2
                  CONTENTS, ALLOC, LOAD, READONLY, DATA
  7 .dma.data     00000240  000000000001d080  000000000001d080  0001e080  2**7
                  CONTENTS, ALLOC, LOAD, DATA
$ cat /sys/kernel/debug/memblock/reserved
   0: 0x0000000000000000..0x0000000000011fff
   1: 0x000000000001b1c8..0x000000000001d2bf
...

Also add alignment before _edma linker symbol definition, so that entire
.dma* region is rounded up to page boundaries.
$ objdump -h arch/s390/boot/compressed/vmlinux
  5 .dma.text     00001000  000000000001c000  000000000001c000  0001d000  2**2
                  CONTENTS, ALLOC, LOAD, READONLY, CODE
  6 .dma.ex_table 00000018  000000000001d000  000000000001d000  0001e000  2**2
                  CONTENTS, ALLOC, LOAD, READONLY, DATA
  7 .dma.data     00000240  000000000001d080  000000000001d080  0001e080  2**7
                  CONTENTS, ALLOC, LOAD, DATA
$ cat /sys/kernel/debug/memblock/reserved
   0: 0x0000000000000000..0x0000000000011fff
   1: 0x000000000001c000..0x000000000001dfff
...
$ cat /sys/kernel/debug/kernel_page_tables
---[ Identity Mapping ]---
0x0000000000000000-0x000000000001c000       112K PTE RW NX
0x000000000001c000-0x000000000001d000         4K PTE RO X
0x000000000001d000-0x0000000000100000       908K PTE RW NX
...

Reviewed-by: Gerald Schaefer <gerald.schaefer@de.ibm.com>
Signed-off-by: Vasily Gorbik <gor@linux.ibm.com>
2019-08-21 12:58:53 +02:00
Vasily Gorbik
19413fe04f s390/startup: purge obsolete .gitignore patterns
sizes.h and vmlinux.scr.lds are not generated since commit 369f91c374
("s390/decompressor: rework uncompressed image info collection").

vmlinux.bin.full is not generated since commit 183ab05ff2 ("s390: get
rid of the first mb of uncompressed image").

Signed-off-by: Vasily Gorbik <gor@linux.ibm.com>
2019-08-21 12:41:43 +02:00
Martin Schwidefsky
8db16d1911 s390/boot: fix compiler error due to missing awk strtonum
The strtonum awk function is a GNU extension and is not available with
all versions of awk. The link of bzImage fails with this error message:

>> awk: line 2: function or never defined
>> awk: line 2: function strtonum never defined
   objcopy: --pad-to: bad number: arch/s390/boot/compressed/vmlinux

Drop the awk script and the --pad-to objcopy parameter it generated and
use a FILL pattern with an appropriate alignment in the linker script
for the arch/s390/boot/compressed/vmlinux file.

Fixes: f678068652 ("s390/boot: pad bzImage to 4K")
Reported-by: kbuild test robot <lkp@intel.com>
Suggested-by: Vasily Gorbik <gor@linux.ibm.com>
Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
2019-05-07 14:37:14 +02:00
Gerald Schaefer
a80313ff91 s390/kernel: introduce .dma sections
With a relocatable kernel that could reside at any place in memory, code
and data that has to stay below 2 GB needs special handling.

This patch introduces .dma sections for such text, data and ex_table.
The sections will be part of the decompressor kernel, so they will not
be relocated and stay below 2 GB. Their location is passed over to the
decompressed / relocated kernel via the .boot.preserved.data section.

The duald and aste for control register setup also need to stay below
2 GB, so move the setup code from arch/s390/kernel/head64.S to
arch/s390/boot/head.S. The duct and linkage_stack could reside above
2 GB, but their content has to be preserved for the decompresed kernel,
so they are also moved into the .dma section.

The start and end address of the .dma sections is added to vmcoreinfo,
for crash support, to help debugging in case the kernel crashed there.

Signed-off-by: Gerald Schaefer <gerald.schaefer@de.ibm.com>
Reviewed-by: Philipp Rudo <prudo@linux.ibm.com>
Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
2019-04-29 10:47:10 +02:00
Gerald Schaefer
805bc0bc23 s390/kernel: build a relocatable kernel
This patch adds support for building a relocatable kernel with -fPIE.
The kernel will be relocated to 0 early in the boot process.

Signed-off-by: Gerald Schaefer <gerald.schaefer@de.ibm.com>
Reviewed-by: Philipp Rudo <prudo@linux.ibm.com>
Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
2019-04-29 10:47:10 +02:00
Gerald Schaefer
bf9921a9c1 s390: introduce .boot.preserved.data section
Introduce .boot.preserve.data section which is similar to .boot.data and
"shared" between the decompressor code and the decompressed kernel. The
decompressor will store values in it, and copy over to the decompressed
image before starting it. This method allows to avoid using pre-defined
addresses and other hacks to pass values between those boot phases.

Unlike .boot.data section .boot.preserved.data is NOT a part of init data,
and hence will be preserved for the kernel life time.

Signed-off-by: Gerald Schaefer <gerald.schaefer@de.ibm.com>
Signed-off-by: Vasily Gorbik <gor@linux.ibm.com>
Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
2019-04-10 17:47:09 +02:00
Masahiro Yamada
5d680056cb s390: make built-in.a not directly depend on *.o.chkbss files
When I was refactoring cmd_ar_builtin in scripts/Makefile.build,
I noticed the build breakage of s390.

Some Makefiles of s390 add extra dependencies to built-in.a;
built-in.a depends on timestamp files *.o.chkbss, but $(AR) does
not want to include them into built-in.a.

Insert a phony target 'chkbss' in between so that $(AR) can take
$(filter-out $(PHONY), $^) as input.

While I was here, I refactored Makefile.chkbss a little bit.

Signed-off-by: Masahiro Yamada <yamada.masahiro@socionext.com>
Acked-by: Heiko Carstens <heiko.carstens@de.ibm.com>
2019-01-28 09:11:17 +09:00
Vasily Gorbik
5a2e1853d6 s390: avoid vmlinux segments overlap
Currently .vmlinux.info section of uncompressed vmlinux elf image is
included into the data segment and load address specified as 0. That
extends data segment to address 0 and makes "text" and "data" segments
overlap.
Program Headers:
  Type           Offset             VirtAddr           PhysAddr
                 FileSiz            MemSiz              Flags  Align
  LOAD           0x0000000000001000 0x0000000000100000 0x0000000000100000
                 0x0000000000ead03c 0x0000000000ead03c  R E    0x1000
  LOAD           0x0000000000eaf000 0x0000000000000000 0x0000000000000000
                 0x0000000001a13400 0x000000000233b520  RWE    0x1000
  NOTE           0x0000000000eae000 0x0000000000fad000 0x0000000000fad000
                 0x000000000000003c 0x000000000000003c         0x4

 Section to Segment mapping:
  Segment Sections...
   00     .text .notes
   01     .rodata __ksymtab __ksymtab_gpl __ksymtab_strings __param
   __modver .data..ro_after_init __ex_table .data __bug_table .init.text
   .exit.text .exit.data .altinstructions .altinstr_replacement
   .nospec_call_table .nospec_return_table .boot.data .init.data
   .data..percpu .bss .vmlinux.info
   02     .notes

Later when vmlinux.bin is produced from vmlinux, .vmlinux.info section
is removed. But elf vmlinux file, even though it is not bootable anymore,
used for debugging and loadable segments overlap should be avoided.

Utilize special ":NONE" phdr specification to avoid adding .vmlinux.info
into loadable data segment. Also set .vmlinux.info section type to INFO,
which allows to get a not-loadable info CONTENTS section.

Since minimal supported version of binutils 2.20 does not have
--dump-section objcopy option, make .vmlinux.info section loadable during
info.bin creation to get actual section contents.

Reported-by: Philipp Rudo <prudo@linux.ibm.com>
Signed-off-by: Vasily Gorbik <gor@linux.ibm.com>
Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
2018-10-26 10:19:40 +02:00
Vasily Gorbik
ef5febae15 s390/decompressor: add missing FORCE to build targets
According to Documentation/kbuild/makefiles.txt all build targets
using if_changed should use FORCE as well. Add missing FORCE to make
sure vmlinux decompressor targets are rebuild properly when not just
immediate prerequisites have changed but also when build command differs.

Reviewed-by: Philipp Rudo <prudo@linux.ibm.com>
Signed-off-by: Vasily Gorbik <gor@linux.ibm.com>
Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
2018-10-26 10:19:40 +02:00
Vasily Gorbik
0a9b40911b s390/kasan: avoid instrumentation of early C code
Instrumented C code cannot run without the kasan shadow area. Exempt
source code files from kasan which are running before / used during
kasan initialization.

Reviewed-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
Signed-off-by: Vasily Gorbik <gor@linux.ibm.com>
Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
2018-10-09 11:21:17 +02:00
Vasily Gorbik
d1b52a4388 s390: introduce .boot.data section
Introduce .boot.data section which is "shared" between the decompressor
code and the decompressed kernel. The decompressor will store values in
it, and copy over to the decompressed image before starting it. This
method allows to avoid using pre-defined addresses and other hacks to
pass values between those boot phases.

.boot.data section is a part of init data, and will be freed after kernel
initialization is complete.

For uncompressed kernel image, .boot.data section is basically the same
as .init.data

Reviewed-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
Signed-off-by: Vasily Gorbik <gor@linux.ibm.com>
Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
2018-10-09 11:21:06 +02:00
Vasily Gorbik
7516fc11e4 s390/decompressor: clean up and rename compressed/misc.c
Since compressed/misc.c is conditionally compiled move error reporting
code to boot/main.c. With that being done compressed/misc.c has no
"miscellaneous" functions left and is all about plain decompression
now. Rename it accordingly.

Reviewed-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
Signed-off-by: Vasily Gorbik <gor@linux.ibm.com>
Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
2018-10-09 11:21:05 +02:00
Vasily Gorbik
15426ca43d s390: rescue initrd as early as possible
To avoid multi-stage initrd rescue operation and to simplify
assumptions during early memory allocations move initrd at some final
safe destination as early as possible. This would also allow us to
drop .bss usage restrictions for some files.

Reviewed-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
Signed-off-by: Vasily Gorbik <gor@linux.ibm.com>
Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
2018-10-09 11:21:05 +02:00
Vasily Gorbik
a2ac1bb1f3 s390/decompressor: get rid of .bss usage
Using .bss in early code should be avoided. It might overlay initrd
image or not yet be initialized. Clean up the last couple of places in
the decompressor's code where .bss is used and enfore no .bss usage
check on boot/compressed/misc.c. In particular:
- initializing free_mem_ptr and free_mem_end_ptr with values guarantee
that these variables won't end up in the .bss section.
- define STATIC_RW_DATA to go into .data section.

Reviewed-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
Signed-off-by: Vasily Gorbik <gor@linux.ibm.com>
Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
2018-10-09 11:21:03 +02:00
Vasily Gorbik
369f91c374 s390/decompressor: rework uncompressed image info collection
The kernel decompressor has to know several bits of information about
uncompressed image. Currently this info is collected by running "nm" on
uncompressed vmlinux + "sed" and producing sizes.h file. This method
worked well, but it has several disadvantages. Obscure symbols name
pattern matching is fragile. Adding new values makes pattern even
longer. Logic is spread across code and make file. Limited ability to
adjust symbols values (currently magic lma value of 0x100000 is always
subtracted). Apart from that same pieces of information (and more)
would be needed for early memory detection and features like KASLR
outside of boot/compressed/ folder where sizes.h is generated.

To overcome limitations new "struct vmlinux_info" has been introduced
to include values needed for the decompressor and the rest of the
boot code. The only static instance of vmlinux_info is produced during
vmlinux link step by filling in struct fields by the linker (like it is
done with input_data in boot/compressed/vmlinux.scr.lds.S). This way
individual values could be adjusted with all the knowledge linker has
and arithmetic it supports. Later .vmlinux.info section (which contains
struct vmlinux_info) is transplanted into the decompressor image and
dropped from uncompressed image altogether.

While doing that replace "compressed/vmlinux.scr.lds.S" linker
script (whose purpose is to rename .data section in piggy.o to
.rodata.compressed) with plain objcopy command. And simplify
decompressor's linker script.

Reviewed-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
Signed-off-by: Vasily Gorbik <gor@linux.ibm.com>
Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
2018-10-09 11:21:02 +02:00
Vasily Gorbik
8f75582a2f s390: remove decompressor's head.S
Decompressor's head.S provided "data mover" sole purpose of which has
been to safely move uncompressed kernel at 0x100000 and jump to it.

With current bzImage layout entire decompressor's code guaranteed to be
in a safe location under 0x100000, and hence could not be overwritten
during kernel move. For that reason head.S could be replaced with simple
memmove function. To do so introduce early boot code phase which is
executed from arch/s390/boot/head.S after "verify_facilities" and takes
care of optional kernel image decompression and transition to it.

Reviewed-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
Signed-off-by: Vasily Gorbik <gor@linux.ibm.com>
Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
2018-10-09 11:21:02 +02:00
Vasily Gorbik
4e62d45885 s390: clean up stacks setup
Replace hard coded stack frame overhead values with STACK_FRAME_OVERHEAD
definition. Avoid unnecessary arithmetic instructions.

Signed-off-by: Vasily Gorbik <gor@linux.ibm.com>
Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
2018-09-20 13:20:29 +02:00
Vasily Gorbik
2d6f74f797 s390/decompressor: correct EXCLUDE_FILE construct
The following linker construct is problematic with linkers of
binutils < 2.28:

EXCLUDE_FILE (*piggy.o) *(.rodata.*)

from 8f1732fc2a11dc of binutils:
"though the linker accepts this without complaint the
EXCLUDE_FILE part is silently ignored and has no effect."

Silent ignoring of EXCLUDE_FILE construct made .rodata.compressed be
part of .rodata, and in case of .rodata.compressed following some
unaligned data, input_len would also become unaligned.

from arch/s390/boot/compressed/vmlinux.map:
 .rodata.compressed
                0x0000000000012fea   0x4d57e7 arch/s390/boot/compressed/piggy.o
                0x0000000000012fea                input_len
                0x0000000000012fee                input_data

input_len is later used here:
arch/s390/boot/compressed/misc.c:113
	__decompress(input_data, input_len, NULL, NULL, output, 0, NULL, error);

asm generated by gcc looks like:
	.loc 3 113 0
egfrl	%r11,input_len

from what assembler generates invalid (the second operand must be aligned
on a doubleword boundary):
   0x00000000000129b4 <+148>:   c4 bc 00 00 03 1b       lgfrl   %r11,0x12fea
hence specification exception is recognized.

To avoid an issue use EXCLUDE_FILE construct which is recognized by
older linkers (since at least binutils-2_11)
	*(EXCLUDE_FILE (*piggy.o) .rodata.compressed)

Also ensure that .rodata.compressed is at least doubleword aligned.

Fixes: 89b5202e81 ("s390/decompressor: support uncompressed kernel")
Reported-by: Halil Pasic <pasic@linux.ibm.com>
Acked-by: Heiko Carstens <heiko.carstens@de.ibm.com>
Signed-off-by: Vasily Gorbik <gor@linux.ibm.com>
Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
2018-07-02 11:25:01 +02:00
Vasily Gorbik
183ab05ff2 s390: get rid of the first mb of uncompressed image
Instead of generating uncompressed kernel image starting at 0, filling
first mb with zeros (with ".org 0x100000") and then trimming it off
from vmlinux.bin before compression, simply generate a kernel image
starting from 0x100000.

Reviewed-by: Heiko Carstens <heiko.carstens@de.ibm.com>
Signed-off-by: Vasily Gorbik <gor@linux.ibm.com>
Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
2018-07-02 11:24:58 +02:00
Vasily Gorbik
4778dc08ef s390/decompressor: discard ___kcrctab section
___kcrctab section is not used during the decompressor phase and could be
discarded to save the memory. It is currently generated due to lib/mem.S
usage, which exports few symbols.

Acked-by: Heiko Carstens <heiko.carstens@de.ibm.com>
Signed-off-by: Vasily Gorbik <gor@linux.ibm.com>
Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
2018-07-02 11:24:56 +02:00
Vasily Gorbik
89b5202e81 s390/decompressor: support uncompressed kernel
Implement uncompressed kernel support (when "None" is picked in kernel
compression mode list). In that case an actual decompression code is
skipped and control is passed from boot/head.S to startup_continue in
kernel/head64.S. To achieve that uncompressed kernel payload is
conditionally put at 0x100000 in bzImage.

In reality this is very close to classic uncompressed kernel "image",
but the decompressor has its own build and link process,
kernel/head64.S lives at 0x100000 rather than at 0x11000, and .bss
section is reused for both stages.

Reviewed-by: Heiko Carstens <heiko.carstens@de.ibm.com>
Signed-off-by: Vasily Gorbik <gor@linux.ibm.com>
Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
2018-06-25 10:14:40 +02:00
Vasily Gorbik
c98b6c679a s390/decompressor: allow to pack uncompressed vmlinux.bin into piggy.o
If none of compression methods defined, leave suffix-y empty, so that
plain uncompressed vmlinux.bin could be reused instead.

Reviewed-by: Heiko Carstens <heiko.carstens@de.ibm.com>
Signed-off-by: Vasily Gorbik <gor@linux.ibm.com>
Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
2018-06-25 10:14:40 +02:00
Vasily Gorbik
b8326bf52e s390/decompressor: allow preprocessor in piggy.o linker script
Rename vmlinux.scr to vmlinux.scr.lds.S and add it to build rules to
enable preprocessor for it.

Also add vmlinux.scr.lds to local .gitignore

Reviewed-by: Heiko Carstens <heiko.carstens@de.ibm.com>
Signed-off-by: Vasily Gorbik <gor@linux.ibm.com>
Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
2018-06-25 10:14:40 +02:00
Vasily Gorbik
0580bce131 s390/decompressor: extend .bss check for early code
Cover the decompressor code with no .bss usage compile time check.

Reviewed-by: Heiko Carstens <heiko.carstens@de.ibm.com>
Signed-off-by: Vasily Gorbik <gor@linux.ibm.com>
Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
2018-06-25 10:14:40 +02:00
Vasily Gorbik
4560ff1386 s390/decompressor: avoid repeating objects list in Makefile
Optimize the decompressor's Makefile to have a single objects list.

Reviewed-by: Heiko Carstens <heiko.carstens@de.ibm.com>
Signed-off-by: Vasily Gorbik <gor@linux.ibm.com>
Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
2018-06-25 10:14:39 +02:00
Vasily Gorbik
cad5b35da9 s390/decompressor: reuse lib/mem.S for mem functions
Reusing arch/s390/lib/mem.S file solves a problem that sclp_early_core.c
and its dependencies have to be compiled with -march=z900 (no need to
compile compressed/misc.c with -march=z900). This also allows to avoid
mem functions duplicates, makes code a bit smaller and optimized mem
functions are utilized.

Reviewed-by: Heiko Carstens <heiko.carstens@de.ibm.com>
Signed-off-by: Vasily Gorbik <gor@linux.ibm.com>
Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
2018-06-25 10:14:39 +02:00
Vasily Gorbik
a1d7d91f10 s390/decompressor: avoid reusing uncompressed image objects
Re-compile ebcdic.c and sclp_early_core.c for the decompressor,
using proper decompressor CFLAGS. This also allows to potentially use
instrumentation for those files when built for the main kernel image.

With kbuild there is no easy way to re-compile a source file from
another directory. Bypass ugly rules and Makefile meta-programming
with relative path includes of original files.

Reviewed-by: Heiko Carstens <heiko.carstens@de.ibm.com>
Signed-off-by: Vasily Gorbik <gor@linux.ibm.com>
Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
2018-06-25 10:14:39 +02:00
Vasily Gorbik
a5802353b1 s390/decompressor: rename entry point to startup_decompressor
Rename the decompressor entry point to startup_decompressor to
avoid confusion, leaving startup_continue as the entry point of the
uncompressed image.

Also remove obsolete comment, as the decompressor code is
unconditionally called from boot/head.S now.

Reviewed-by: Heiko Carstens <heiko.carstens@de.ibm.com>
Signed-off-by: Vasily Gorbik <gor@linux.ibm.com>
Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
2018-06-25 10:14:38 +02:00
Vasily Gorbik
8282cd64d0 s390/boot: make head.S and als.c be part of the decompressor only
Since uncompressed kernel image does not have to be bootable anymore,
move head.S, head_kdump.S and als.c to boot/ folder and compile them
in just in the decompressor.

Reviewed-by: Heiko Carstens <heiko.carstens@de.ibm.com>
Signed-off-by: Vasily Gorbik <gor@linux.ibm.com>
Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
2018-06-25 10:14:38 +02:00
Vasily Gorbik
bd79d66329 s390/decompressor: trim the kernel image up to 1M
Move head64.S main kernel entry point "startup_continue" to 0x100000 and
trim everything which is below 1M during build. So, that the decompressor
would unpack the main kernel image, move it to 0x100000 and jump to
startup_continue.

Reviewed-by: Heiko Carstens <heiko.carstens@de.ibm.com>
Signed-off-by: Vasily Gorbik <gor@linux.ibm.com>
Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
2018-06-25 10:14:38 +02:00
Vasily Gorbik
76bf9d6cef s390/decompressor: correct build flags
The decompressor requires its own set of cc and asm flags, to avoid
building with features which do not make sense at such an early boot stage
(e.g. expoline, ftrace).

Currently cc flags are already set for the decompressor, but "cflags-y"
is not exported and hence empty. To fix that and to add asm flags, define
and export KBUILD_AFLAGS_DECOMPRESSOR and KBUILD_CFLAGS_DECOMPRESSOR
and rely on them in the decompressor's Makefile.

Reviewed-by: Heiko Carstens <heiko.carstens@de.ibm.com>
Signed-off-by: Vasily Gorbik <gor@linux.ibm.com>
Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
2018-06-25 10:14:37 +02:00
Thomas Richter
701e188c65 s390/decompressor: Ignore file vmlinux.bin.full
Commit 81796a3c6a ("s390/decompressor: trim uncompressed
image head during the build") introduced a new
file named vmlinux.bin.full in directory
arch/s390/boot/compressed.

Add this file to the list of ignored files so it does
not show up on git status.

Signed-off-by: Thomas Richter <tmricht@linux.ibm.com>
Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
2018-04-16 09:10:23 +02:00
Vasily Gorbik
d08091ac96 s390/ipl: rely on diag308 store to get ipl info
For both ccw and fcp boot retrieve ipl info from ipl block received via
diag308 store. Old scsi ipl parm block handling and cio_get_iplinfo are
removed. Ipl type is deducted from ipl block (if valid).

Reviewed-by: Heiko Carstens <heiko.carstens@de.ibm.com>
Signed-off-by: Vasily Gorbik <gor@linux.ibm.com>
Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
2018-04-10 07:38:59 +02:00
Vasily Gorbik
81796a3c6a s390/decompressor: trim uncompressed image head during the build
It seems to be suboptimal to compress the entire image, so that we
could decompress and throw away the first 68k (0x11000) during the boot
process. This patch trims 0x11000 bytes during the build process and
adjusts symbols in size.h accordingly.

Besides making bzImage smaller, this change would also be a benefit
for kaslr. It allows to decompress the kernel right to desired offset,
without worrying about dead weight in front of the decompressed image.

Signed-off-by: Vasily Gorbik <gor@linux.vnet.ibm.com>
Acked-by: Heiko Carstens <heiko.carstens@de.ibm.com>
Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
2018-03-18 23:02:07 -07:00
Vasily Gorbik
320d9555cb s390: unify linker symbols usage
Common code defines linker symbols which denote sections start/end in
a form of char []. Referencing those symbols as _symbol or &_symbol
yields the same result, but "_symbol" form is more widespread across
newly written code. Convert s390 specific code to this style.

Also removes unused _text symbol definition in boot/compressed/misc.c.

Signed-off-by: Vasily Gorbik <gor@linux.vnet.ibm.com>
Acked-by: Heiko Carstens <heiko.carstens@de.ibm.com>
Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
2018-02-27 08:05:23 +01:00
Vasily Gorbik
3ad6b25013 s390/decompressor: discard __ex_table section
Exception table (__ex_table section) is not used during the decompressor
phase and could be discarded to save the memory. It is currently
generated due to sclp_service_call function (sclp_early_core.c). An
assumption is that decompressor usage of sclp_service_call via
sclp_early_printk should never trigger exceptions.

Signed-off-by: Vasily Gorbik <gor@linux.vnet.ibm.com>
Acked-by: Heiko Carstens <heiko.carstens@de.ibm.com>
Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
2018-02-27 08:05:21 +01:00
Vasily Gorbik
47d67facb0 s390/decompressor: discard __ksymtab and .eh_frame sections
__ksymtab sections created for exported symbols are not needed
during the decompressor phase and could be discarded to save the memory.
The source of those exports is ebcdic.o, which is linked into both
vmlinux and boot/compressed/vmlinux.

.eh_frame section is also unused and could be discarded from
boot/compressed/vmlinux. The same has been done for vmlinux in:
"s390/kernel: emit CFI data in .debug_frame and discard .eh_frame
sections".

Signed-off-by: Vasily Gorbik <gor@linux.vnet.ibm.com>
Reviewed-by: Hendrik Brueckner <brueckner@linux.vnet.ibm.com>
Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
2018-01-23 07:36:54 +01:00
Vasily Gorbik
a5daf0e3ea s390/decompressor: swap .text and .rodata.compressed sections
.rodata.compressed section contains compressed linux image and is
quite large. By swapping text and rodata.compressed sections, the
decompressor code ends up between 0x11000 and 0x100000 addresses,
which makes it easier:
- to distinguish the decompressor phase from decompressed code (which
lives above 0x100000, except for small startup_continue),
- define break points which don't intersect with the main kernel image
later.

Signed-off-by: Vasily Gorbik <gor@linux.vnet.ibm.com>
Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
2018-01-23 07:36:49 +01:00
Martin Schwidefsky
9fa1db4c75 s390: add a few more SPDX identifiers
Add the correct SPDX license to a few more files under arch/s390 and
drivers/s390 which have been missed to far.
The SPDX identifier is a legally binding shorthand, which can be used
instead of the full boiler plate text.

Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
2017-12-05 07:51:09 +01:00
Linus Torvalds
d60a540ac5 Merge branch 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/s390/linux
Pull s390 updates from Heiko Carstens:
 "Since Martin is on vacation you get the s390 pull request for the
  v4.15 merge window this time from me.

  Besides a lot of cleanups and bug fixes these are the most important
  changes:

   - a new regset for runtime instrumentation registers

   - hardware accelerated AES-GCM support for the aes_s390 module

   - support for the new CEX6S crypto cards

   - support for FORTIFY_SOURCE

   - addition of missing z13 and new z14 instructions to the in-kernel
     disassembler

   - generate opcode tables for the in-kernel disassembler out of a
     simple text file instead of having to manually maintain those
     tables

   - fast memset16, memset32 and memset64 implementations

   - removal of named saved segment support

   - hardware counter support for z14

   - queued spinlocks and queued rwlocks implementations for s390

   - use the stack_depth tracking feature for s390 BPF JIT

   - a new s390_sthyi system call which emulates the sthyi (store
     hypervisor information) instruction

   - removal of the old KVM virtio transport

   - an s390 specific CPU alternatives implementation which is used in
     the new spinlock code"

* 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/s390/linux: (88 commits)
  MAINTAINERS: add virtio-ccw.h to virtio/s390 section
  s390/noexec: execute kexec datamover without DAT
  s390: fix transactional execution control register handling
  s390/bpf: take advantage of stack_depth tracking
  s390: simplify transactional execution elf hwcap handling
  s390/zcrypt: Rework struct ap_qact_ap_info.
  s390/virtio: remove unused header file kvm_virtio.h
  s390: avoid undefined behaviour
  s390/disassembler: generate opcode tables from text file
  s390/disassembler: remove insn_to_mnemonic()
  s390/dasd: avoid calling do_gettimeofday()
  s390: vfio-ccw: Do not attempt to free no-op, test and tic cda.
  s390: remove named saved segment support
  s390/archrandom: Reconsider s390 arch random implementation
  s390/pci: do not require AIS facility
  s390/qdio: sanitize put_indicator
  s390/qdio: use atomic_cmpxchg
  s390/nmi: avoid using long-displacement facility
  s390: pass endianness info to sparse
  s390/decompressor: remove informational messages
  ...
2017-11-13 11:47:01 -08:00