From 980d5f9ab36b6cfe473a8371a7e11bd168c9e630 Mon Sep 17 00:00:00 2001 From: Alexander Egorenkov Date: Wed, 2 Sep 2020 16:52:06 +0200 Subject: [PATCH] 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 Reviewed-by: Vasily Gorbik Signed-off-by: Vasily Gorbik --- arch/s390/boot/Makefile | 4 ---- arch/s390/boot/compressed/Makefile | 4 ---- arch/s390/boot/compressed/decompressor.c | 1 - arch/s390/boot/compressed/vmlinux.lds.S | 22 +++++++++++++--------- arch/s390/boot/head.S | 6 ++++++ arch/s390/boot/ipl_parm.c | 4 ++-- arch/s390/boot/startup.c | 3 +++ arch/s390/kernel/setup.c | 2 +- arch/s390/scripts/Makefile.chkbss | 20 -------------------- 9 files changed, 25 insertions(+), 41 deletions(-) delete mode 100644 arch/s390/scripts/Makefile.chkbss diff --git a/arch/s390/boot/Makefile b/arch/s390/boot/Makefile index 45b33b8..41a64b8 100644 --- a/arch/s390/boot/Makefile +++ b/arch/s390/boot/Makefile @@ -73,7 +73,3 @@ $(obj)/startup.a: $(OBJECTS) FORCE install: sh -x $(srctree)/$(obj)/install.sh $(KERNELRELEASE) $(obj)/bzImage \ System.map "$(INSTALL_PATH)" - -chkbss := $(obj-y) -chkbss-target := startup.a -include $(srctree)/arch/s390/scripts/Makefile.chkbss diff --git a/arch/s390/boot/compressed/Makefile b/arch/s390/boot/compressed/Makefile index fa529c5..b235ed95 100644 --- a/arch/s390/boot/compressed/Makefile +++ b/arch/s390/boot/compressed/Makefile @@ -62,7 +62,3 @@ $(obj)/vmlinux.bin.xz: $(vmlinux.bin.all-y) FORCE OBJCOPYFLAGS_piggy.o := -I binary -O elf64-s390 -B s390:64-bit --rename-section .data=.vmlinux.bin.compressed $(obj)/piggy.o: $(obj)/vmlinux.bin$(suffix-y) FORCE $(call if_changed,objcopy) - -chkbss := $(filter-out piggy.o info.o, $(obj-y)) -chkbss-target := vmlinux.bin -include $(srctree)/arch/s390/scripts/Makefile.chkbss diff --git a/arch/s390/boot/compressed/decompressor.c b/arch/s390/boot/compressed/decompressor.c index 368fd37..3061b11 100644 --- a/arch/s390/boot/compressed/decompressor.c +++ b/arch/s390/boot/compressed/decompressor.c @@ -16,7 +16,6 @@ * gzip declarations */ #define STATIC static -#define STATIC_RW_DATA static __section(.data) #undef memset #undef memcpy diff --git a/arch/s390/boot/compressed/vmlinux.lds.S b/arch/s390/boot/compressed/vmlinux.lds.S index 44561b2..9427e2c 100644 --- a/arch/s390/boot/compressed/vmlinux.lds.S +++ b/arch/s390/boot/compressed/vmlinux.lds.S @@ -59,6 +59,19 @@ SECTIONS BOOT_DATA_PRESERVED /* + * This is the BSS section of the decompressor and not of the decompressed Linux kernel. + * It will consume place in the decompressor's image. + */ + . = ALIGN(8); + .bss : { + _bss = . ; + *(.bss) + *(.bss.*) + *(COMMON) + _ebss = .; + } + + /* * uncompressed image info used by the decompressor it should match * struct vmlinux_info. It comes from .vmlinux.info section of * uncompressed vmlinux in a form of info.o @@ -81,15 +94,6 @@ SECTIONS FILL(0xff); . = ALIGN(4096); } - . = ALIGN(256); - .bss : { - _bss = . ; - *(.bss) - *(.bss.*) - *(COMMON) - . = ALIGN(8); /* For convenience during zeroing */ - _ebss = .; - } _end = .; /* Sections to be discarded */ diff --git a/arch/s390/boot/head.S b/arch/s390/boot/head.S index dae1096..fd78755 100644 --- a/arch/s390/boot/head.S +++ b/arch/s390/boot/head.S @@ -313,6 +313,12 @@ ENTRY(startup_kdump) spt 6f-.LPG0(%r13) mvc __LC_LAST_UPDATE_TIMER(8),6f-.LPG0(%r13) l %r15,.Lstack-.LPG0(%r13) + // Clear decompressor's BSS section + larl %r2,_bss + slgr %r3,%r3 + larl %r4,_ebss + slgr %r4,%r2 + brasl %r14,memset brasl %r14,verify_facilities brasl %r14,startup_kernel diff --git a/arch/s390/boot/ipl_parm.c b/arch/s390/boot/ipl_parm.c index 8e222a6..ae230eb 100644 --- a/arch/s390/boot/ipl_parm.c +++ b/arch/s390/boot/ipl_parm.c @@ -21,7 +21,7 @@ unsigned long __bootdata(memory_end); int __bootdata(memory_end_set); int __bootdata(noexec_disabled); -int kaslr_enabled __section(.data); +int kaslr_enabled; static inline int __diag308(unsigned long subcode, void *addr) { @@ -209,7 +209,7 @@ static void modify_fac_list(char *str) check_cleared_facilities(); } -static char command_line_buf[COMMAND_LINE_SIZE] __section(.data); +static char command_line_buf[COMMAND_LINE_SIZE]; void parse_boot_command_line(void) { char *param, *val; diff --git a/arch/s390/boot/startup.c b/arch/s390/boot/startup.c index 3b3a11f..8183548 100644 --- a/arch/s390/boot/startup.c +++ b/arch/s390/boot/startup.c @@ -120,6 +120,9 @@ static void handle_relocs(unsigned long offset) } } +/* + * This function clears the BSS section of the decompressed Linux kernel and NOT the decompressor's. + */ static void clear_bss_section(void) { memset((void *)vmlinux.default_lma + vmlinux.image_size, 0, vmlinux.bss_size); diff --git a/arch/s390/kernel/setup.c b/arch/s390/kernel/setup.c index f04252c..0477939 100644 --- a/arch/s390/kernel/setup.c +++ b/arch/s390/kernel/setup.c @@ -307,7 +307,7 @@ void machine_power_off(void) void (*pm_power_off)(void) = machine_power_off; EXPORT_SYMBOL_GPL(pm_power_off); -void *restart_stack __section(.data); +void *restart_stack; unsigned long stack_alloc(void) { diff --git a/arch/s390/scripts/Makefile.chkbss b/arch/s390/scripts/Makefile.chkbss deleted file mode 100644 index f4f4c2c..0000000 --- a/arch/s390/scripts/Makefile.chkbss +++ /dev/null @@ -1,20 +0,0 @@ -# SPDX-License-Identifier: GPL-2.0 - -chkbss-target ?= built-in.a -$(obj)/$(chkbss-target): chkbss - -chkbss-files := $(addsuffix .chkbss, $(chkbss)) -clean-files += $(chkbss-files) - -PHONY += chkbss -chkbss: $(addprefix $(obj)/, $(chkbss-files)) - -quiet_cmd_chkbss = CHKBSS $< - cmd_chkbss = \ - if ! $(OBJSIZE) --common $< | $(AWK) 'END { if ($$3) exit 1 }'; then \ - echo "error: $< .bss section is not empty" >&2; exit 1; \ - fi; \ - touch $@; - -$(obj)/%.o.chkbss: $(obj)/%.o - $(call cmd,chkbss) -- 2.7.4