Need ensure the cma reserved region not cross the low/high memory boundary
when using the dynamic allocation methond through device-tree, otherwise,
kernel will fail to boot up when cma reserved region cross how/high mem.
Signed-off-by: Jason Liu <[email protected]>
Cc: Laura Abbott <[email protected]>
Cc: Frank Rowand <[email protected]>
Cc: Rob Herring <[email protected]>
Cc: [email protected]
---
drivers/of/of_reserved_mem.c | 42 +++++++++++++++++++++++++++++++----------
include/linux/of_reserved_mem.h | 3 ++-
2 files changed, 34 insertions(+), 11 deletions(-)
diff --git a/drivers/of/of_reserved_mem.c b/drivers/of/of_reserved_mem.c
index 366d8c3..852345a 100644
--- a/drivers/of/of_reserved_mem.c
+++ b/drivers/of/of_reserved_mem.c
@@ -31,11 +31,15 @@
#if defined(CONFIG_HAVE_MEMBLOCK)
#include <linux/memblock.h>
-int __init __weak early_init_dt_alloc_reserved_memory_arch(phys_addr_t size,
- phys_addr_t align, phys_addr_t start, phys_addr_t end, bool nomap,
- phys_addr_t *res_base)
+int __init __weak early_init_dt_alloc_reserved_memory_arch(unsigned long node,
+ phys_addr_t size, phys_addr_t align, phys_addr_t start, phys_addr_t end,
+ bool nomap, phys_addr_t *res_base)
{
phys_addr_t base;
+ phys_addr_t highmem_start;
+
+ highmem_start = __pa(high_memory - 1) + 1;
+
/*
* We use __memblock_alloc_base() because memblock_alloc_base()
* panic()s on allocation failure.
@@ -53,15 +57,33 @@ int __init __weak early_init_dt_alloc_reserved_memory_arch(phys_addr_t size,
return -ENOMEM;
}
+ /*
+ * Sanity check for the cma reserved region:If the reserved region
+ * crosses the low/high memory boundary, try to fix it up and then
+ * fall back to allocate the cma region from the low mememory space.
+ */
+
+ if (IS_ENABLED(CONFIG_CMA)
+ && of_flat_dt_is_compatible(node, "shared-dma-pool")
+ && of_get_flat_dt_prop(node, "reusable", NULL) && !nomap) {
+ if (base < highmem_start && (base + size) > highmem_start) {
+ memblock_free(base, size);
+ base = memblock_alloc_range(size, align, start,
+ highmem_start, MEMBLOCK_NONE);
+ if (!base)
+ return -ENOMEM;
+ }
+ }
+
*res_base = base;
if (nomap)
return memblock_remove(base, size);
return 0;
}
#else
-int __init __weak early_init_dt_alloc_reserved_memory_arch(phys_addr_t size,
- phys_addr_t align, phys_addr_t start, phys_addr_t end, bool nomap,
- phys_addr_t *res_base)
+int __init __weak early_init_dt_alloc_reserved_memory_arch(unsigned long node,
+ phys_addr_t size, phys_addr_t align, phys_addr_t start, phys_addr_t end,
+ bool nomap, phys_addr_t *res_base)
{
pr_err("Reserved memory not supported, ignoring region 0x%llx%s\n",
size, nomap ? " (nomap)" : "");
@@ -155,8 +177,8 @@ static int __init __reserved_mem_alloc_size(unsigned long node,
end = start + dt_mem_next_cell(dt_root_size_cells,
&prop);
- ret = early_init_dt_alloc_reserved_memory_arch(size,
- align, start, end, nomap, &base);
+ ret = early_init_dt_alloc_reserved_memory_arch(node,
+ size, align, start, end, nomap, &base);
if (ret == 0) {
pr_debug("allocated memory for '%s' node: base %pa, size %ld MiB\n",
uname, &base,
@@ -167,8 +189,8 @@ static int __init __reserved_mem_alloc_size(unsigned long node,
}
} else {
- ret = early_init_dt_alloc_reserved_memory_arch(size, align,
- 0, 0, nomap, &base);
+ ret = early_init_dt_alloc_reserved_memory_arch(node,
+ size, align, 0, 0, nomap, &base);
if (ret == 0)
pr_debug("allocated memory for '%s' node: base %pa, size %ld MiB\n",
uname, &base, (unsigned long)size / SZ_1M);
diff --git a/include/linux/of_reserved_mem.h b/include/linux/of_reserved_mem.h
index f8e1992..a6ee451 100644
--- a/include/linux/of_reserved_mem.h
+++ b/include/linux/of_reserved_mem.h
@@ -34,7 +34,8 @@ int of_reserved_mem_device_init_by_idx(struct device *dev,
struct device_node *np, int idx);
void of_reserved_mem_device_release(struct device *dev);
-int early_init_dt_alloc_reserved_memory_arch(phys_addr_t size,
+int early_init_dt_alloc_reserved_memory_arch(unsigned long node,
+ phys_addr_t size,
phys_addr_t align,
phys_addr_t start,
phys_addr_t end,
--
1.8.3.2
2016-11-23 19:37 GMT+08:00 Jason Liu <[email protected]>:
> Need ensure the cma reserved region not cross the low/high memory boundary
> when using the dynamic allocation methond through device-tree, otherwise,
> kernel will fail to boot up when cma reserved region cross how/high mem.
>
> Signed-off-by: Jason Liu <[email protected]>
> Cc: Laura Abbott <[email protected]>
> Cc: Frank Rowand <[email protected]>
> Cc: Rob Herring <[email protected]>
> Cc: [email protected]
> ---
> drivers/of/of_reserved_mem.c | 42 +++++++++++++++++++++++++++++++----------
> include/linux/of_reserved_mem.h | 3 ++-
> 2 files changed, 34 insertions(+), 11 deletions(-)
Rob, any comments about this patch?
Jason Liu
>
> diff --git a/drivers/of/of_reserved_mem.c b/drivers/of/of_reserved_mem.c
> index 366d8c3..852345a 100644
> --- a/drivers/of/of_reserved_mem.c
> +++ b/drivers/of/of_reserved_mem.c
> @@ -31,11 +31,15 @@
>
> #if defined(CONFIG_HAVE_MEMBLOCK)
> #include <linux/memblock.h>
> -int __init __weak early_init_dt_alloc_reserved_memory_arch(phys_addr_t size,
> - phys_addr_t align, phys_addr_t start, phys_addr_t end, bool nomap,
> - phys_addr_t *res_base)
> +int __init __weak early_init_dt_alloc_reserved_memory_arch(unsigned long node,
> + phys_addr_t size, phys_addr_t align, phys_addr_t start, phys_addr_t end,
> + bool nomap, phys_addr_t *res_base)
> {
> phys_addr_t base;
> + phys_addr_t highmem_start;
> +
> + highmem_start = __pa(high_memory - 1) + 1;
> +
> /*
> * We use __memblock_alloc_base() because memblock_alloc_base()
> * panic()s on allocation failure.
> @@ -53,15 +57,33 @@ int __init __weak early_init_dt_alloc_reserved_memory_arch(phys_addr_t size,
> return -ENOMEM;
> }
>
> + /*
> + * Sanity check for the cma reserved region:If the reserved region
> + * crosses the low/high memory boundary, try to fix it up and then
> + * fall back to allocate the cma region from the low mememory space.
> + */
> +
> + if (IS_ENABLED(CONFIG_CMA)
> + && of_flat_dt_is_compatible(node, "shared-dma-pool")
> + && of_get_flat_dt_prop(node, "reusable", NULL) && !nomap) {
> + if (base < highmem_start && (base + size) > highmem_start) {
> + memblock_free(base, size);
> + base = memblock_alloc_range(size, align, start,
> + highmem_start, MEMBLOCK_NONE);
> + if (!base)
> + return -ENOMEM;
> + }
> + }
> +
> *res_base = base;
> if (nomap)
> return memblock_remove(base, size);
> return 0;
> }
> #else
> -int __init __weak early_init_dt_alloc_reserved_memory_arch(phys_addr_t size,
> - phys_addr_t align, phys_addr_t start, phys_addr_t end, bool nomap,
> - phys_addr_t *res_base)
> +int __init __weak early_init_dt_alloc_reserved_memory_arch(unsigned long node,
> + phys_addr_t size, phys_addr_t align, phys_addr_t start, phys_addr_t end,
> + bool nomap, phys_addr_t *res_base)
> {
> pr_err("Reserved memory not supported, ignoring region 0x%llx%s\n",
> size, nomap ? " (nomap)" : "");
> @@ -155,8 +177,8 @@ static int __init __reserved_mem_alloc_size(unsigned long node,
> end = start + dt_mem_next_cell(dt_root_size_cells,
> &prop);
>
> - ret = early_init_dt_alloc_reserved_memory_arch(size,
> - align, start, end, nomap, &base);
> + ret = early_init_dt_alloc_reserved_memory_arch(node,
> + size, align, start, end, nomap, &base);
> if (ret == 0) {
> pr_debug("allocated memory for '%s' node: base %pa, size %ld MiB\n",
> uname, &base,
> @@ -167,8 +189,8 @@ static int __init __reserved_mem_alloc_size(unsigned long node,
> }
>
> } else {
> - ret = early_init_dt_alloc_reserved_memory_arch(size, align,
> - 0, 0, nomap, &base);
> + ret = early_init_dt_alloc_reserved_memory_arch(node,
> + size, align, 0, 0, nomap, &base);
> if (ret == 0)
> pr_debug("allocated memory for '%s' node: base %pa, size %ld MiB\n",
> uname, &base, (unsigned long)size / SZ_1M);
> diff --git a/include/linux/of_reserved_mem.h b/include/linux/of_reserved_mem.h
> index f8e1992..a6ee451 100644
> --- a/include/linux/of_reserved_mem.h
> +++ b/include/linux/of_reserved_mem.h
> @@ -34,7 +34,8 @@ int of_reserved_mem_device_init_by_idx(struct device *dev,
> struct device_node *np, int idx);
> void of_reserved_mem_device_release(struct device *dev);
>
> -int early_init_dt_alloc_reserved_memory_arch(phys_addr_t size,
> +int early_init_dt_alloc_reserved_memory_arch(unsigned long node,
> + phys_addr_t size,
> phys_addr_t align,
> phys_addr_t start,
> phys_addr_t end,
> --
> 1.8.3.2
>
On Wed, Nov 23, 2016 at 5:37 AM, Jason Liu <[email protected]> wrote:
> Need ensure the cma reserved region not cross the low/high memory boundary
> when using the dynamic allocation methond through device-tree, otherwise,
> kernel will fail to boot up when cma reserved region cross how/high mem.
The kernel command line code setting CMA already deals with this. Why
don't we just call the CMA code (cma_declare_contiguous) to deal with
this?
Rob
On 12/14/2016 12:45 PM, Rob Herring wrote:
> On Wed, Nov 23, 2016 at 5:37 AM, Jason Liu <[email protected]> wrote:
>> Need ensure the cma reserved region not cross the low/high memory boundary
>> when using the dynamic allocation methond through device-tree, otherwise,
>> kernel will fail to boot up when cma reserved region cross how/high mem.
>
> The kernel command line code setting CMA already deals with this. Why
> don't we just call the CMA code (cma_declare_contiguous) to deal with
> this?
>
> Rob
>
That was proposed in the first version[1] but I think this is a generic
problem not specific to CMA. Even non-CMA reservations trying to span
zones could cause problems so the devicetree allocation code should
restrict reservations to a single zone.
Thanks,
Laura
[1] https://marc.info/?l=linux-kernel&m=147928325113103&w=2
On Wed, Dec 14, 2016 at 4:21 PM, Laura Abbott <[email protected]> wrote:
> On 12/14/2016 12:45 PM, Rob Herring wrote:
>> On Wed, Nov 23, 2016 at 5:37 AM, Jason Liu <[email protected]> wrote:
>>> Need ensure the cma reserved region not cross the low/high memory boundary
>>> when using the dynamic allocation methond through device-tree, otherwise,
>>> kernel will fail to boot up when cma reserved region cross how/high mem.
>>
>> The kernel command line code setting CMA already deals with this. Why
>> don't we just call the CMA code (cma_declare_contiguous) to deal with
>> this?
>>
>> Rob
>>
>
> That was proposed in the first version[1] but I think this is a generic
> problem not specific to CMA. Even non-CMA reservations trying to span
> zones could cause problems so the devicetree allocation code should
> restrict reservations to a single zone.
Fair enough, but that's not what this patch does. It's only for CMA.
Rob
2016-12-15 21:54 GMT+08:00 Rob Herring <[email protected]>:
> On Wed, Dec 14, 2016 at 4:21 PM, Laura Abbott <[email protected]> wrote:
>> On 12/14/2016 12:45 PM, Rob Herring wrote:
>>> On Wed, Nov 23, 2016 at 5:37 AM, Jason Liu <[email protected]> wrote:
>>>> Need ensure the cma reserved region not cross the low/high memory boundary
>>>> when using the dynamic allocation methond through device-tree, otherwise,
>>>> kernel will fail to boot up when cma reserved region cross how/high mem.
>>>
>>> The kernel command line code setting CMA already deals with this. Why
>>> don't we just call the CMA code (cma_declare_contiguous) to deal with
>>> this?
>>>
>>> Rob
>>>
>>
>> That was proposed in the first version[1] but I think this is a generic
>> problem not specific to CMA. Even non-CMA reservations trying to span
>> zones could cause problems so the devicetree allocation code should
>> restrict reservations to a single zone.
>
> Fair enough, but that's not what this patch does. It's only for CMA.
I'm only certain that the CMA reservation from the device-tree is not
working now.
and if you guys think that this is not only the CMA but also other
non-CMA reservations
should also have this restriction on the device-tree method. I can
change the patch the patch
as the followings.
diff --git a/drivers/of/of_reserved_mem.c b/drivers/of/of_reserved_mem.c
index 366d8c3..7b8857d 100644
--- a/drivers/of/of_reserved_mem.c
+++ b/drivers/of/of_reserved_mem.c
@@ -31,11 +31,15 @@ static int reserved_mem_count;
#if defined(CONFIG_HAVE_MEMBLOCK)
#include <linux/memblock.h>
-int __init __weak early_init_dt_alloc_reserved_memory_arch(phys_addr_t size,
- phys_addr_t align, phys_addr_t start, phys_addr_t end, bool nomap,
- phys_addr_t *res_base)
+int __init __weak early_init_dt_alloc_reserved_memory_arch(unsigned long node,
+ phys_addr_t size, phys_addr_t align, phys_addr_t start, phys_addr_t end,
+ bool nomap, phys_addr_t *res_base)
{
phys_addr_t base;
+ phys_addr_t highmem_start;
+
+ highmem_start = __pa(high_memory - 1) + 1;
+
/*
* We use __memblock_alloc_base() because memblock_alloc_base()
* panic()s on allocation failure.
@@ -53,15 +57,29 @@ int __init __weak
early_init_dt_alloc_reserved_memory_arch(phys_addr_t size,
return -ENOMEM;
}
+ /*
+ * Sanity check for the reserved region:If the reserved region
+ * crosses the low/high memory boundary, try to fix it up and then
+ * fall back to allocate region from the low mememory space.
+ */
+
+ if (base < highmem_start && (base + size) > highmem_start) {
+ memblock_free(base, size);
+ base = memblock_alloc_range(size, align, start,
+ highmem_start, MEMBLOCK_NONE);
+ if (!base)
+ return -ENOMEM;
+ }
+
if you guys have good idea, please share or post your patch. This is
really an issue
that reserve memory from the device-tree is broken.
>
> Rob