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powerpc/fadump: pass additional parameters when fadump is active

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Append the additional parameters passed/set in the dedicated parameter
area (RTAS_FADUMP_PARAM_AREA) to bootargs in fadump capture kernel.

Signed-off-by: Hari Bathini <hbathini@linux.ibm.com>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
Link: https://msgid.link/20240509115755.519982-4-hbathini@linux.ibm.com
This commit is contained in:
Hari Bathini 2024-05-09 17:27:55 +05:30 committed by Michael Ellerman
parent 683eab94da
commit 3416c9daa6
3 changed files with 40 additions and 0 deletions
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2
arch/powerpc/include/asm/fadump.h
View file

@ -19,12 +19,14 @@ extern int is_fadump_active(void);
extern int should_fadump_crash(void);
extern void crash_fadump(struct pt_regs *, const char *);
extern void fadump_cleanup(void);
extern void fadump_append_bootargs(void);
#else /* CONFIG_FA_DUMP */
static inline int is_fadump_active(void) { return 0; }
static inline int should_fadump_crash(void) { return 0; }
static inline void crash_fadump(struct pt_regs *regs, const char *str) { }
static inline void fadump_cleanup(void) { }
static inline void fadump_append_bootargs(void) { }
#endif /* !CONFIG_FA_DUMP */
#if defined(CONFIG_FA_DUMP) || defined(CONFIG_PRESERVE_FA_DUMP)

35
arch/powerpc/kernel/fadump.c
View file

@ -131,6 +131,41 @@ static int __init fadump_cma_init(void)
static int __init fadump_cma_init(void) { return 1; }
#endif /* CONFIG_CMA */
/*
* Additional parameters meant for capture kernel are placed in a dedicated area.
* If this is capture kernel boot, append these parameters to bootargs.
*/
void __init fadump_append_bootargs(void)
{
char *append_args;
size_t len;
if (!fw_dump.dump_active || !fw_dump.param_area_supported || !fw_dump.param_area)
return;
if (fw_dump.param_area >= fw_dump.boot_mem_top) {
if (memblock_reserve(fw_dump.param_area, COMMAND_LINE_SIZE)) {
pr_warn("WARNING: Can't use additional parameters area!\n");
fw_dump.param_area = 0;
return;
}
}
append_args = (char *)fw_dump.param_area;
len = strlen(boot_command_line);
/*
* Too late to fail even if cmdline size exceeds. Truncate additional parameters
* to cmdline size and proceed anyway.
*/
if (len + strlen(append_args) >= COMMAND_LINE_SIZE - 1)
pr_warn("WARNING: Appending parameters exceeds cmdline size. Truncating!\n");
pr_debug("Cmdline: %s\n", boot_command_line);
snprintf(boot_command_line + len, COMMAND_LINE_SIZE - len, " %s", append_args);
pr_info("Updated cmdline: %s\n", boot_command_line);
}
/* Scan the Firmware Assisted dump configuration details. */
int __init early_init_dt_scan_fw_dump(unsigned long node, const char *uname,
int depth, void *data)

3
arch/powerpc/kernel/prom.c
View file

@ -813,6 +813,9 @@ void __init early_init_devtree(void *params)
*/
of_scan_flat_dt(early_init_dt_scan_chosen_ppc, boot_command_line);
/* Append additional parameters passed for fadump capture kernel */
fadump_append_bootargs();
/* Scan memory nodes and rebuild MEMBLOCKs */
early_init_dt_scan_root();
early_init_dt_scan_memory_ppc();