diff mbox

[v7,01/17] arm64: allow late use of early_ioremap

Message ID 1421247905-3749-2-git-send-email-hanjun.guo@linaro.org (mailing list archive)
State New, archived
Headers show

Commit Message

Hanjun Guo Jan. 14, 2015, 3:04 p.m. UTC 
From: Mark Salter <msalter@redhat.com>

Commit 0e63ea48b4d8 (arm64/efi: add missing call to early_ioremap_reset())
added a missing call to early_ioremap_reset(). This triggers a BUG if code
tries using early_ioremap() after the early_ioremap_reset(). This is a
problem for some ACPI code which needs short-lived temporary mappings
after paging_init() but before acpi_early_init() in start_kernel(). This
patch adds definitions for the __late_set_fixmap() and __late_clear_fixmap()
which avoids the BUG by allowing later use of early_ioremap().

Signed-off-by: Mark Salter <msalter@redhat.com>
CC: Leif Lindholm <leif.lindholm@linaro.org>
CC: Ard Biesheuvel <ard.biesheuvel@linaro.org>
[hj: update the change log]
Signed-off-by: Hanjun Guo <hanjun.guo@linaro.org>
---
 arch/arm64/include/asm/fixmap.h | 3 +++
 1 file changed, 3 insertions(+)

Comments

Mark Langsdorf Jan. 15, 2015, 6:44 p.m. UTC | #1 
On 01/14/2015 09:04 AM, Hanjun Guo wrote:
> From: Mark Salter <msalter@redhat.com>
>
> Commit 0e63ea48b4d8 (arm64/efi: add missing call to early_ioremap_reset())
> added a missing call to early_ioremap_reset(). This triggers a BUG if code
> tries using early_ioremap() after the early_ioremap_reset(). This is a
> problem for some ACPI code which needs short-lived temporary mappings
> after paging_init() but before acpi_early_init() in start_kernel(). This
> patch adds definitions for the __late_set_fixmap() and __late_clear_fixmap()
> which avoids the BUG by allowing later use of early_ioremap().
>
> Signed-off-by: Mark Salter <msalter@redhat.com>
> CC: Leif Lindholm <leif.lindholm@linaro.org>
> CC: Ard Biesheuvel <ard.biesheuvel@linaro.org>
> [hj: update the change log]
> Signed-off-by: Hanjun Guo <hanjun.guo@linaro.org>
> ---
Tested-by: Mark Langsdorf <mlangsdo@redhat.com>
diff mbox

Patch

diff --git a/arch/arm64/include/asm/fixmap.h b/arch/arm64/include/asm/fixmap.h
index 9ef6eca..e629c70 100644
--- a/arch/arm64/include/asm/fixmap.h
+++ b/arch/arm64/include/asm/fixmap.h
@@ -61,6 +61,9 @@  void __init early_fixmap_init(void);
 
 #define __early_set_fixmap __set_fixmap
 
+#define __late_set_fixmap __set_fixmap
+#define __late_clear_fixmap(idx) __set_fixmap((idx), 0, FIXMAP_PAGE_CLEAR)
+
 extern void __set_fixmap(enum fixed_addresses idx, phys_addr_t phys, pgprot_t prot);
 
 #include <asm-generic/fixmap.h>