diff mbox series

[4/4] xen/arm: Introduce fw_unreserved_regions() and use it

Message ID 20200926205542.9261-5-julien@xen.org (mailing list archive)
State Superseded
Headers show
Series xen/arm: Unbreak ACPI | expand

Commit Message

Julien Grall Sept. 26, 2020, 8:55 p.m. UTC
From: Julien Grall <jgrall@amazon.com>

Since commit 6e3e77120378 "xen/arm: setup: Relocate the Device-Tree
later on in the boot", the device-tree will not be kept mapped when
using ACPI.

However, a few places are calling dt_unreserved_regions() which expects
a valid DT. This will lead to a crash.

As the DT should not be used for ACPI (other than for detecting the
modules), a new function fw_unreserved_regions() is introduced.

It will behave the same way on DT system. On ACPI system, it will
unreserve the whole region.

Signed-off-by: Julien Grall <jgrall@amazon.com>

---

Is there any region we should exclude on ACPI?
---
 xen/arch/arm/kernel.c       |  2 +-
 xen/arch/arm/setup.c        | 22 +++++++++++++++++-----
 xen/include/asm-arm/setup.h |  2 +-
 3 files changed, 19 insertions(+), 7 deletions(-)

Comments

Stefano Stabellini Sept. 30, 2020, 11:40 p.m. UTC | #1
On Sat, 26 Sep 2020, Julien Grall wrote:
> From: Julien Grall <jgrall@amazon.com>
> 
> Since commit 6e3e77120378 "xen/arm: setup: Relocate the Device-Tree
> later on in the boot", the device-tree will not be kept mapped when
> using ACPI.
> 
> However, a few places are calling dt_unreserved_regions() which expects
> a valid DT. This will lead to a crash.
> 
> As the DT should not be used for ACPI (other than for detecting the
> modules), a new function fw_unreserved_regions() is introduced.
> 
> It will behave the same way on DT system. On ACPI system, it will
> unreserve the whole region.

The patch is good.

Reviewed-by: Stefano Stabellini <sstabellini@kernel.org>


I have a small suggestion for improvement that could be done on commit:
given that bootinfo is actually used on EFI systems (granted, not
bootinfo.reserved_mem but bootinfo.mem, see
xen/arch/arm/efi/efi-boot.h:efi_process_memory_map_bootinfo) so
technically bootinfo could be in-use with ACPI, maybe we could add a
comment on top of xen/include/asm-arm/setup.h:bootinfo to say that
reserved_mem is device tree only?



> Signed-off-by: Julien Grall <jgrall@amazon.com>
> 
> ---
> 
> Is there any region we should exclude on ACPI?
> ---
>  xen/arch/arm/kernel.c       |  2 +-
>  xen/arch/arm/setup.c        | 22 +++++++++++++++++-----
>  xen/include/asm-arm/setup.h |  2 +-
>  3 files changed, 19 insertions(+), 7 deletions(-)
> 
> diff --git a/xen/arch/arm/kernel.c b/xen/arch/arm/kernel.c
> index 032923853f2c..ab78689ed2a6 100644
> --- a/xen/arch/arm/kernel.c
> +++ b/xen/arch/arm/kernel.c
> @@ -307,7 +307,7 @@ static __init int kernel_decompress(struct bootmodule *mod)
>       * Free the original kernel, update the pointers to the
>       * decompressed kernel
>       */
> -    dt_unreserved_regions(addr, addr + size, init_domheap_pages, 0);
> +    fw_unreserved_regions(addr, addr + size, init_domheap_pages, 0);
>  
>      return 0;
>  }
> diff --git a/xen/arch/arm/setup.c b/xen/arch/arm/setup.c
> index 35e5bee04efa..7fcff9af2a7e 100644
> --- a/xen/arch/arm/setup.c
> +++ b/xen/arch/arm/setup.c
> @@ -196,8 +196,9 @@ static void __init processor_id(void)
>      processor_setup();
>  }
>  
> -void __init dt_unreserved_regions(paddr_t s, paddr_t e,
> -                                  void (*cb)(paddr_t, paddr_t), int first)
> +static void __init dt_unreserved_regions(paddr_t s, paddr_t e,
> +                                         void (*cb)(paddr_t, paddr_t),
> +                                         int first)
>  {
>      int i, nr = fdt_num_mem_rsv(device_tree_flattened);
>  
> @@ -244,6 +245,17 @@ void __init dt_unreserved_regions(paddr_t s, paddr_t e,
>      cb(s, e);
>  }
>  
> +void __init fw_unreserved_regions(paddr_t s, paddr_t e,
> +                                  void (*cb)(paddr_t, paddr_t), int first)
> +{
> +    if ( acpi_disabled )
> +        dt_unreserved_regions(s, e, cb, first);
> +    else
> +        cb(s, e);
> +}
> +
> +
> +
>  struct bootmodule __init *add_boot_module(bootmodule_kind kind,
>                                            paddr_t start, paddr_t size,
>                                            bool domU)
> @@ -405,7 +417,7 @@ void __init discard_initial_modules(void)
>               !mfn_valid(maddr_to_mfn(e)) )
>              continue;
>  
> -        dt_unreserved_regions(s, e, init_domheap_pages, 0);
> +        fw_unreserved_regions(s, e, init_domheap_pages, 0);
>      }
>  
>      mi->nr_mods = 0;
> @@ -712,7 +724,7 @@ static void __init setup_mm(void)
>                  n = mfn_to_maddr(mfn_add(xenheap_mfn_start, xenheap_pages));
>              }
>  
> -            dt_unreserved_regions(s, e, init_boot_pages, 0);
> +            fw_unreserved_regions(s, e, init_boot_pages, 0);
>  
>              s = n;
>          }
> @@ -765,7 +777,7 @@ static void __init setup_mm(void)
>              if ( e > bank_end )
>                  e = bank_end;
>  
> -            dt_unreserved_regions(s, e, init_boot_pages, 0);
> +            fw_unreserved_regions(s, e, init_boot_pages, 0);
>              s = n;
>          }
>      }
> diff --git a/xen/include/asm-arm/setup.h b/xen/include/asm-arm/setup.h
> index 2f8f24e286ed..34df23247b87 100644
> --- a/xen/include/asm-arm/setup.h
> +++ b/xen/include/asm-arm/setup.h
> @@ -96,7 +96,7 @@ int construct_dom0(struct domain *d);
>  void create_domUs(void);
>  
>  void discard_initial_modules(void);
> -void dt_unreserved_regions(paddr_t s, paddr_t e,
> +void fw_unreserved_regions(paddr_t s, paddr_t e,
>                             void (*cb)(paddr_t, paddr_t), int first);
>  
>  size_t boot_fdt_info(const void *fdt, paddr_t paddr);
> -- 
> 2.17.1
>
Julien Grall Oct. 1, 2020, 3:34 p.m. UTC | #2
Hi Stefano,

On 01/10/2020 00:40, Stefano Stabellini wrote:
> On Sat, 26 Sep 2020, Julien Grall wrote:
> I have a small suggestion for improvement that could be done on commit:
> given that bootinfo is actually used on EFI systems (granted, not
> bootinfo.reserved_mem but bootinfo.mem, see
> xen/arch/arm/efi/efi-boot.h:efi_process_memory_map_bootinfo) so
> technically bootinfo could be in-use with ACPI, maybe we could add a
> comment on top of xen/include/asm-arm/setup.h:bootinfo to say that
> reserved_mem is device tree only?

That's fine with me. I will need to resend the rest of the series, so I 
will update it at the same time.

Cheers,
diff mbox series

Patch

diff --git a/xen/arch/arm/kernel.c b/xen/arch/arm/kernel.c
index 032923853f2c..ab78689ed2a6 100644
--- a/xen/arch/arm/kernel.c
+++ b/xen/arch/arm/kernel.c
@@ -307,7 +307,7 @@  static __init int kernel_decompress(struct bootmodule *mod)
      * Free the original kernel, update the pointers to the
      * decompressed kernel
      */
-    dt_unreserved_regions(addr, addr + size, init_domheap_pages, 0);
+    fw_unreserved_regions(addr, addr + size, init_domheap_pages, 0);
 
     return 0;
 }
diff --git a/xen/arch/arm/setup.c b/xen/arch/arm/setup.c
index 35e5bee04efa..7fcff9af2a7e 100644
--- a/xen/arch/arm/setup.c
+++ b/xen/arch/arm/setup.c
@@ -196,8 +196,9 @@  static void __init processor_id(void)
     processor_setup();
 }
 
-void __init dt_unreserved_regions(paddr_t s, paddr_t e,
-                                  void (*cb)(paddr_t, paddr_t), int first)
+static void __init dt_unreserved_regions(paddr_t s, paddr_t e,
+                                         void (*cb)(paddr_t, paddr_t),
+                                         int first)
 {
     int i, nr = fdt_num_mem_rsv(device_tree_flattened);
 
@@ -244,6 +245,17 @@  void __init dt_unreserved_regions(paddr_t s, paddr_t e,
     cb(s, e);
 }
 
+void __init fw_unreserved_regions(paddr_t s, paddr_t e,
+                                  void (*cb)(paddr_t, paddr_t), int first)
+{
+    if ( acpi_disabled )
+        dt_unreserved_regions(s, e, cb, first);
+    else
+        cb(s, e);
+}
+
+
+
 struct bootmodule __init *add_boot_module(bootmodule_kind kind,
                                           paddr_t start, paddr_t size,
                                           bool domU)
@@ -405,7 +417,7 @@  void __init discard_initial_modules(void)
              !mfn_valid(maddr_to_mfn(e)) )
             continue;
 
-        dt_unreserved_regions(s, e, init_domheap_pages, 0);
+        fw_unreserved_regions(s, e, init_domheap_pages, 0);
     }
 
     mi->nr_mods = 0;
@@ -712,7 +724,7 @@  static void __init setup_mm(void)
                 n = mfn_to_maddr(mfn_add(xenheap_mfn_start, xenheap_pages));
             }
 
-            dt_unreserved_regions(s, e, init_boot_pages, 0);
+            fw_unreserved_regions(s, e, init_boot_pages, 0);
 
             s = n;
         }
@@ -765,7 +777,7 @@  static void __init setup_mm(void)
             if ( e > bank_end )
                 e = bank_end;
 
-            dt_unreserved_regions(s, e, init_boot_pages, 0);
+            fw_unreserved_regions(s, e, init_boot_pages, 0);
             s = n;
         }
     }
diff --git a/xen/include/asm-arm/setup.h b/xen/include/asm-arm/setup.h
index 2f8f24e286ed..34df23247b87 100644
--- a/xen/include/asm-arm/setup.h
+++ b/xen/include/asm-arm/setup.h
@@ -96,7 +96,7 @@  int construct_dom0(struct domain *d);
 void create_domUs(void);
 
 void discard_initial_modules(void);
-void dt_unreserved_regions(paddr_t s, paddr_t e,
+void fw_unreserved_regions(paddr_t s, paddr_t e,
                            void (*cb)(paddr_t, paddr_t), int first);
 
 size_t boot_fdt_info(const void *fdt, paddr_t paddr);