[PATCH v11 3/5] x86/earlyprintk: Allocate early log_buf as early as possible

Alexander Kuleshov
2015-06-09T11:12:07Z

This patch moves call of the early setup_log_buf from the
arch/x86/kernel/setup.c to the arch/x86/kernel/head{32,64}.c
and updates log_buf with the earlyprintk messages.

We need to do it because without it we will not see earlyprintk
messages in the kernel log.

Signed-off-by: Alexander Kuleshov <kuleshovmail@gmail.com>
---
arch/x86/kernel/head32.c | 6 ++++++
arch/x86/kernel/head64.c | 5 +++++
arch/x86/kernel/setup.c | 3 ---
kernel/printk/printk.c | 5 +++++
4 files changed, 16 insertions(+), 3 deletions(-)

diff --git a/arch/x86/kernel/head32.c b/arch/x86/kernel/head32.c
index 92e8b5f..f28d10f 100644
--- a/arch/x86/kernel/head32.c
+++ b/arch/x86/kernel/head32.c
@@ -32,2 +32,2 @@ static void __init i386_default_early_setup(void)
asmlinkage __visible void __init i386_start_kernel(void)
{
setup_builtin_cmdline();
+
+ lockdep_init();
+
+ /* Allocate early log buffer */
+ setup_log_buf(1);
+
cr4_init_shadow();
sanitize_boot_params(&boot_params);

diff --git a/arch/x86/kernel/head64.c b/arch/x86/kernel/head64.c
index 1e5f064..53662d2 100644
--- a/arch/x86/kernel/head64.c
+++ b/arch/x86/kernel/head64.c
@@ -174,0 +174,0 @@ asmlinkage __visible void __init x86_64_start_kernel(char * real_mode_data)

setup_builtin_cmdline();

+ lockdep_init();
+
+ /* Allocate early log buffer */
+ setup_log_buf(1);
+
/*
* Load microcode early on BSP.
*/
diff --git a/arch/x86/kernel/setup.c b/arch/x86/kernel/setup.c
index 0aeee0a..edfdb6a 100644
--- a/arch/x86/kernel/setup.c
+++ b/arch/x86/kernel/setup.c
@@ -1146,9 +1146,6 @@ void __init setup_arch(char **cmdline_p)
if (init_ohci1394_dma_early)
init_ohci1394_dma_on_all_controllers();
#endif
- /* Allocate bigger log buffer */
- setup_log_buf(1);
-
reserve_initrd();

#if defined(CONFIG_ACPI) && defined(CONFIG_BLK_DEV_INITRD)
diff --git a/kernel/printk/printk.c b/kernel/printk/printk.c
index c099b08..d76a032 100644
--- a/kernel/printk/printk.c
+++ b/kernel/printk/printk.c
@@ -1913,6 +1913,7 @@ asmlinkage __visible void early_printk(const char *fmt, ...)
va_list ap;
char buf[512];
int n;
+ printk_func_t vprintk_func;

if (!early_console)
return;
@@ -1922,7 +1923,10 @@ asmlinkage __visible void early_printk(const char *fmt, ...)
va_end(ap);

early_console->write(early_console, buf, n);
+
+ /* Store earlyprintk messages in the log_buf */
+ vprintk_func = this_cpu_read(printk_func);
+ vprintk_func(fmt, ap);
}
#endif

--
2.4.0.GIT