Donate to e Foundation | Murena handsets with /e/OS | Own a part of Murena! Learn more

Commit 653beba2 authored by Philipp Rudo's avatar Philipp Rudo Committed by Martin Schwidefsky
Browse files

s390/kexec_file: Load new kernel to absolute 0 



The leading 64 kB of a kernel image doesn't contain any data needed to boot
the new kernel when it was loaded via kexec_file. Thus kexec_file currently
strips them off before loading the image. Keep the leading 64 kB in order
to be able to pass a ipl_report to the next kernel.

Signed-off-by: default avatarPhilipp Rudo <prudo@linux.ibm.com>
Signed-off-by: default avatarMartin Schwidefsky <schwidefsky@de.ibm.com>
parent 8e496426

arch/s390/include/asm/kexec.h

+6 −0
Original line number Diff line number Diff line
@@ -43,6 +43,9 @@ 
/* The native architecture */

#define KEXEC_ARCH KEXEC_ARCH_S390



/* Allow kexec_file to load a segment to 0 */

#define KEXEC_BUF_MEM_UNKNOWN -1



/* Provide a dummy definition to avoid build failures. */

static inline void crash_setup_regs(struct pt_regs *newregs,

					struct pt_regs *oldregs) { }
@@ -52,6 +55,9 @@ struct s390_load_data { 
	/* Pointer to the kernel buffer. Used to register cmdline etc.. */

	void *kernel_buf;



	/* Load address of the kernel_buf. */

	unsigned long kernel_mem;



	/* Parmarea in the kernel buffer. */

	struct parmarea *parm;

arch/s390/kernel/kexec_elf.c

+4 −12
Original line number Diff line number Diff line
@@ -39,28 +39,20 @@ static int kexec_file_add_kernel_elf(struct kimage *image, 
		buf.bufsz = phdr->p_filesz;



		buf.mem = ALIGN(phdr->p_paddr, phdr->p_align);

		if (image->type == KEXEC_TYPE_CRASH)

			buf.mem += crashk_res.start;

		buf.memsz = phdr->p_memsz;

		data->memsz = ALIGN(data->memsz, phdr->p_align) + buf.memsz;



		if (entry - phdr->p_paddr < phdr->p_memsz) {

			data->kernel_buf = buf.buffer;

			data->kernel_mem = buf.mem;

			data->parm = buf.buffer + PARMAREA;

			data->memsz += STARTUP_NORMAL_OFFSET;



			buf.buffer += STARTUP_NORMAL_OFFSET;

			buf.bufsz -= STARTUP_NORMAL_OFFSET;



			buf.mem += STARTUP_NORMAL_OFFSET;

			buf.memsz -= STARTUP_NORMAL_OFFSET;

		}



		if (image->type == KEXEC_TYPE_CRASH)

			buf.mem += crashk_res.start;



		ret = kexec_add_buffer(&buf);

		if (ret)

			return ret;



		data->memsz = ALIGN(data->memsz, phdr->p_align) + buf.memsz;

	}



	return data->memsz ? 0 : -EINVAL;

arch/s390/kernel/kexec_image.c

+5 −4
Original line number Diff line number Diff line
@@ -19,17 +19,18 @@ static int kexec_file_add_kernel_image(struct kimage *image, 


	buf.image = image;



	buf.buffer = image->kernel_buf + STARTUP_NORMAL_OFFSET;

	buf.bufsz = image->kernel_buf_len - STARTUP_NORMAL_OFFSET;

	buf.buffer = image->kernel_buf;

	buf.bufsz = image->kernel_buf_len;



	buf.mem = STARTUP_NORMAL_OFFSET;

	buf.mem = 0;

	if (image->type == KEXEC_TYPE_CRASH)

		buf.mem += crashk_res.start;

	buf.memsz = buf.bufsz;



	data->kernel_buf = image->kernel_buf;

	data->kernel_mem = buf.mem;

	data->parm = image->kernel_buf + PARMAREA;

	data->memsz += buf.memsz + STARTUP_NORMAL_OFFSET;

	data->memsz += buf.memsz;



	return kexec_add_buffer(&buf);

}

arch/s390/kernel/machine_kexec_file.c

+10 −2
Original line number Diff line number Diff line
@@ -17,7 +17,8 @@ const struct kexec_file_ops * const kexec_file_loaders[] = { 
	NULL,

};



static int kexec_file_update_purgatory(struct kimage *image)

static int kexec_file_update_purgatory(struct kimage *image,

				       struct s390_load_data *data)

{

	u64 entry, type;

	int ret;
@@ -76,7 +77,7 @@ static int kexec_file_add_purgatory(struct kimage *image, 
	if (ret)

		return ret;



	ret = kexec_file_update_purgatory(image);

	ret = kexec_file_update_purgatory(image, data);

	return ret;

}
@@ -136,6 +137,13 @@ void *kexec_file_add_components(struct kimage *image, 
	if (ret)

		return ERR_PTR(ret);



	if (data.kernel_mem == 0) {

		unsigned long restart_psw =  0x0008000080000000UL;

		restart_psw += image->start;

		memcpy(data.kernel_buf, &restart_psw, sizeof(restart_psw));

		image->start = 0;

	}



	return NULL;

}

arch/s390/kernel/relocate_kernel.S

+3 −0
Original line number Diff line number Diff line
@@ -58,10 +58,13 @@ ENTRY(relocate_kernel) 
		j	.base

	.done:

		sgr	%r0,%r0		# clear register r0

		cghi	%r3,0

		je	.diag

		la	%r4,load_psw-.base(%r13)	# load psw-address into the register

		o	%r3,4(%r4)	# or load address into psw

		st	%r3,4(%r4)

		mvc	0(8,%r0),0(%r4)	# copy psw to absolute address 0

	.diag:

		diag	%r0,%r0,0x308



		.align	8