wireguard-linux/arch/s390/boot/compressed/vmlinux.lds.S, branch jd/unified-crypt-queue

s390/startup: adjust _sdma and _edma to page boundaries

2019-08-21T10:58:53Z

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 Signed-off-by: Vasily Gorbik

s390/boot: fix compiler error due to missing awk strtonum

2019-05-07T12:37:14Z

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: f6780686525c ("s390/boot: pad bzImage to 4K") Reported-by: kbuild test robot Suggested-by: Vasily Gorbik Signed-off-by: Martin Schwidefsky

s390/kernel: introduce .dma sections

2019-04-29T08:47:10Z

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 Reviewed-by: Philipp Rudo Signed-off-by: Martin Schwidefsky

s390: introduce .boot.preserved.data section

2019-04-10T15:47:09Z

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 Signed-off-by: Vasily Gorbik Signed-off-by: Martin Schwidefsky

s390: introduce .boot.data section

2018-10-09T09:21:06Z

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 Signed-off-by: Vasily Gorbik Signed-off-by: Martin Schwidefsky

s390/decompressor: rework uncompressed image info collection

2018-10-09T09:21:02Z

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 Signed-off-by: Vasily Gorbik Signed-off-by: Martin Schwidefsky

s390/decompressor: correct EXCLUDE_FILE construct

2018-07-02T09:25:01Z

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: 89b5202e81df ("s390/decompressor: support uncompressed kernel") Reported-by: Halil Pasic Acked-by: Heiko Carstens Signed-off-by: Vasily Gorbik Signed-off-by: Martin Schwidefsky

s390/decompressor: discard ___kcrctab section

2018-07-02T09:24:56Z

___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 Signed-off-by: Vasily Gorbik Signed-off-by: Martin Schwidefsky

s390/decompressor: support uncompressed kernel

2018-06-25T08:14:40Z

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 Signed-off-by: Vasily Gorbik Signed-off-by: Martin Schwidefsky

s390/decompressor: discard __ex_table section

2018-02-27T07:05:21Z

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 Acked-by: Heiko Carstens Signed-off-by: Martin Schwidefsky