From fcc1c0ff2506cab8c3a019374550f68b3cbadcbe Mon Sep 17 00:00:00 2001 From: Michal Simek Date: Thu, 16 Aug 2012 15:53:35 +0200 Subject: [PATCH] microblaze: Fix bug with passing command line When u-boot passes control over to Linux it places the Linux command line between to the end of __init_end. When space between __init_end and __bss_start is not COMMAND_LINE_SIZE then the part of cmdline can be lost. In extreme case if __init_end == __bss_start u-boot can't pass any cmdline to Linux kernel. This patch fix this issue by copying cmd line directly to cmd_line char array which is placed in data section. Reported-by: David Mc Andrew Signed-off-by: Michal Simek --- arch/microblaze/kernel/head.S | 14 +++++++++----- arch/microblaze/kernel/setup.c | 13 ++++++------- 2 files changed, 15 insertions(+), 12 deletions(-) diff --git a/arch/microblaze/kernel/head.S b/arch/microblaze/kernel/head.S index 98b17f9f904b..eef84de5e8c8 100644 --- a/arch/microblaze/kernel/head.S +++ b/arch/microblaze/kernel/head.S @@ -109,20 +109,24 @@ no_fdt_arg: #ifndef CONFIG_CMDLINE_BOOL /* * handling command line - * copy command line to __init_end. There is space for storing command line. + * copy command line directly to cmd_line placed in data section. */ + beqid r5, skip /* Skip if NULL pointer */ or r6, r0, r0 /* incremment */ - ori r4, r0, __init_end /* load address of command line */ + ori r4, r0, cmd_line /* load address of command line */ tophys(r4,r4) /* convert to phys address */ ori r3, r0, COMMAND_LINE_SIZE - 1 /* number of loops */ _copy_command_line: - lbu r2, r5, r6 /* r2=r5+r6 - r5 contain pointer to command line */ - sb r2, r4, r6 /* addr[r4+r6]= r2*/ + /* r2=r5+r6 - r5 contain pointer to command line */ + lbu r2, r5, r6 + beqid r2, skip /* Skip if no data */ + sb r2, r4, r6 /* addr[r4+r6]= r2*/ addik r6, r6, 1 /* increment counting */ bgtid r3, _copy_command_line /* loop for all entries */ - addik r3, r3, -1 /* descrement loop */ + addik r3, r3, -1 /* decrement loop */ addik r5, r4, 0 /* add new space for command line */ tovirt(r5,r5) +skip: #endif /* CONFIG_CMDLINE_BOOL */ #ifdef NOT_COMPILE diff --git a/arch/microblaze/kernel/setup.c b/arch/microblaze/kernel/setup.c index 4da971d4392f..9dbc9ecb28f1 100644 --- a/arch/microblaze/kernel/setup.c +++ b/arch/microblaze/kernel/setup.c @@ -40,7 +40,12 @@ DEFINE_PER_CPU(unsigned int, R11_SAVE); /* Temp variable for entry */ DEFINE_PER_CPU(unsigned int, CURRENT_SAVE); /* Saved current pointer */ unsigned int boot_cpuid; -char cmd_line[COMMAND_LINE_SIZE]; +/* + * Placed cmd_line to .data section because can be initialized from + * ASM code. Default position is BSS section which is cleared + * in machine_early_init(). + */ +char cmd_line[COMMAND_LINE_SIZE] __attribute__ ((section(".data"))); void __init setup_arch(char **cmdline_p) { @@ -130,12 +135,6 @@ void __init machine_early_init(const char *cmdline, unsigned int ram, memset(__bss_start, 0, __bss_stop-__bss_start); memset(_ssbss, 0, _esbss-_ssbss); - /* Copy command line passed from bootloader */ -#ifndef CONFIG_CMDLINE_BOOL - if (cmdline && cmdline[0] != '\0') - strlcpy(cmd_line, cmdline, COMMAND_LINE_SIZE); -#endif - lockdep_init(); /* initialize device tree for usage in early_printk */ -- 2.34.1