From 087c4d7423989b110c3312592db05acc009a5d58 Mon Sep 17 00:00:00 2001 From: Gerald Schaefer Date: Mon, 8 Apr 2019 12:49:58 +0200 Subject: s390/sclp: do not use static sccbs The sccbs for init/read/sdias/early have to be located below 2 GB, and they are currently defined as a static buffer. With a relocatable kernel that could reside at any place in memory, this will no longer guarantee the location below 2 GB, so use a dynamic GFP_DMA allocation instead. The sclp_early_sccb buffer needs special handling, as it can be used very early, and by both the decompressor and also the decompressed kernel. Therefore, a fixed 4 KB buffer is introduced at 0x11000, the former PARMAREA_END. The new PARMAREA_END is now 0x12000, and it is renamed to HEAD_END, as it is rather the end of head.S and not the end of the parmarea. Signed-off-by: Gerald Schaefer Reviewed-by: Philipp Rudo Signed-off-by: Martin Schwidefsky --- arch/s390/boot/head.S | 5 ++++- arch/s390/include/asm/setup.h | 5 ++++- arch/s390/kernel/machine_kexec_file.c | 4 +--- arch/s390/kernel/setup.c | 2 +- 4 files changed, 10 insertions(+), 6 deletions(-) (limited to 'arch/s390') diff --git a/arch/s390/boot/head.S b/arch/s390/boot/head.S index d585c4dbdac7..c6b4b4c5dd58 100644 --- a/arch/s390/boot/head.S +++ b/arch/s390/boot/head.S @@ -336,4 +336,7 @@ ENTRY(startup_kdump) .byte "root=/dev/ram0 ro" .byte 0 - .org 0x11000 + .org EARLY_SCCB_OFFSET + .fill 4096 + + .org HEAD_END diff --git a/arch/s390/include/asm/setup.h b/arch/s390/include/asm/setup.h index b603cc09c895..d202756d6291 100644 --- a/arch/s390/include/asm/setup.h +++ b/arch/s390/include/asm/setup.h @@ -12,7 +12,10 @@ #define EP_OFFSET 0x10008 #define EP_STRING "S390EP" #define PARMAREA 0x10400 -#define PARMAREA_END 0x11000 +#define EARLY_SCCB_OFFSET 0x11000 +#define HEAD_END 0x12000 + +#define EARLY_SCCB_SIZE PAGE_SIZE /* * Machine features detected in early.c diff --git a/arch/s390/kernel/machine_kexec_file.c b/arch/s390/kernel/machine_kexec_file.c index 42c23a5c8229..fbdd3ea73667 100644 --- a/arch/s390/kernel/machine_kexec_file.c +++ b/arch/s390/kernel/machine_kexec_file.c @@ -337,10 +337,8 @@ int arch_kexec_kernel_image_probe(struct kimage *image, void *buf, * load memory in head.S will be accessed, e.g. to register the next * command line. If the next kernel were smaller the current kernel * will panic at load. - * - * 0x11000 = sizeof(head.S) */ - if (buf_len < 0x11000) + if (buf_len < HEAD_END) return -ENOEXEC; return kexec_image_probe_default(image, buf, buf_len); diff --git a/arch/s390/kernel/setup.c b/arch/s390/kernel/setup.c index ffc87520aca9..94efb1eb34b6 100644 --- a/arch/s390/kernel/setup.c +++ b/arch/s390/kernel/setup.c @@ -829,7 +829,7 @@ static void __init reserve_kernel(void) { unsigned long start_pfn = PFN_UP(__pa(_end)); - memblock_reserve(0, PARMAREA_END); + memblock_reserve(0, HEAD_END); memblock_reserve((unsigned long)_stext, PFN_PHYS(start_pfn) - (unsigned long)_stext); } -- cgit v1.2.3