earlyprintk=efi,keep will cause kernel hangs while freeing initmem like below:
[    2.826089] VFS: Mounted root (ext4 filesystem) readonly on device 254:2.
[    2.846592] devtmpfs: mounted
[    2.856974] Freeing unused kernel memory: 880K (ffffffff817d4000 - 
ffffffff818b0000)

It is caused by efi earlyprintk use __init function which will be freed later.
Such as early_efi_write is marked as __init, also it will use early_ioremap
which is init function as well.

To fix this issue, I added one early initcall efi_ioremap_fb which will map the 
whole
efi fb for later use. OTOH, adding a wrapper function efi_ioremap which will 
call
early_ioremap before ioremap is available.

With this patch applied efi boot ok with earlyprintk=efi,keep console=efi

Signed-off-by: Dave Young <dyo...@redhat.com>
---
 arch/x86/platform/efi/early_printk.c |   54 +++++++++++++++++++++++++++--------
 1 file changed, 42 insertions(+), 12 deletions(-)

--- linux-2.6.orig/arch/x86/platform/efi/early_printk.c
+++ linux-2.6/arch/x86/platform/efi/early_printk.c
@@ -14,8 +14,38 @@
 
 static const struct font_desc *font;
 static u32 efi_x, efi_y;
+static void *efi_fb;
 
-static __init void early_efi_clear_scanline(unsigned int y)
+static __init int efi_ioremap_fb(void)
+{
+       unsigned long base, size;
+
+       base = boot_params.screen_info.lfb_base;
+       size = boot_params.screen_info.lfb_size;
+       efi_fb = ioremap(base, size);
+
+       return efi_fb ? 0 : -ENOMEM;
+}
+early_initcall(efi_ioremap_fb);
+
+static __init_refok void *efi_ioremap(unsigned long start, unsigned long len)
+{
+       unsigned long base;
+
+       base = boot_params.screen_info.lfb_base;
+       if (efi_fb)
+               return (efi_fb + start - base);
+       else
+               return early_ioremap(start, len);
+}
+
+static __init_refok void efi_iounmap(void *addr, unsigned long len)
+{
+       if (!efi_fb)
+               early_iounmap(addr, len);
+}
+
+static void early_efi_clear_scanline(unsigned int y)
 {
        unsigned long base, *dst;
        u16 len;
@@ -23,15 +53,15 @@ static __init void early_efi_clear_scanl
        base = boot_params.screen_info.lfb_base;
        len = boot_params.screen_info.lfb_linelength;
 
-       dst = early_ioremap(base + y*len, len);
+       dst = efi_ioremap(base + y*len, len);
        if (!dst)
                return;
 
        memset(dst, 0, len);
-       early_iounmap(dst, len);
+       efi_iounmap(dst, len);
 }
 
-static __init void early_efi_scroll_up(void)
+static void early_efi_scroll_up(void)
 {
        unsigned long base, *dst, *src;
        u16 len;
@@ -42,20 +72,20 @@ static __init void early_efi_scroll_up(v
        height = boot_params.screen_info.lfb_height;
 
        for (i = 0; i < height - font->height; i++) {
-               dst = early_ioremap(base + i*len, len);
+               dst = efi_ioremap(base + i*len, len);
                if (!dst)
                        return;
 
-               src = early_ioremap(base + (i + font->height) * len, len);
+               src = efi_ioremap(base + (i + font->height) * len, len);
                if (!src) {
-                       early_iounmap(dst, len);
+                       efi_iounmap(dst, len);
                        return;
                }
 
                memmove(dst, src, len);
 
-               early_iounmap(src, len);
-               early_iounmap(dst, len);
+               efi_iounmap(src, len);
+               efi_iounmap(dst, len);
        }
 }
 
@@ -79,7 +109,7 @@ static void early_efi_write_char(u32 *ds
        }
 }
 
-static __init void
+static void
 early_efi_write(struct console *con, const char *str, unsigned int num)
 {
        struct screen_info *si;
@@ -109,7 +139,7 @@ early_efi_write(struct console *con, con
                for (h = 0; h < font->height; h++) {
                        unsigned int n, x;
 
-                       dst = early_ioremap(base + (efi_y + h) * len, len);
+                       dst = efi_ioremap(base + (efi_y + h) * len, len);
                        if (!dst)
                                return;
 
@@ -123,7 +153,7 @@ early_efi_write(struct console *con, con
                                s++;
                        }
 
-                       early_iounmap(dst, len);
+                       efi_iounmap(dst, len);
                }
 
                num -= count;
--
To unsubscribe from this list: send the line "unsubscribe linux-kernel" in
the body of a message to majord...@vger.kernel.org
More majordomo info at  http://vger.kernel.org/majordomo-info.html
Please read the FAQ at  http://www.tux.org/lkml/

Reply via email to