Add the capability to mark regions of the memory memory_type able of
hardware memory encryption.
Also add the capability to query if all regions of a memory node are
able to do hardware memory encryption to call it when initializing the
nodes. Warn the user if a node has both encryptable and
non-encryptable regions.
Signed-off-by: Martin Fernandez <[email protected]>
---
include/linux/memblock.h | 5 ++++
mm/memblock.c | 62 ++++++++++++++++++++++++++++++++++++++++
2 files changed, 67 insertions(+)
diff --git a/include/linux/memblock.h b/include/linux/memblock.h
index 50ad19662a32..00c4f1a20335 100644
--- a/include/linux/memblock.h
+++ b/include/linux/memblock.h
@@ -40,6 +40,7 @@ extern unsigned long long max_possible_pfn;
* via a driver, and never indicated in the firmware-provided memory map as
* system RAM. This corresponds to IORESOURCE_SYSRAM_DRIVER_MANAGED in the
* kernel resource tree.
+ * @MEMBLOCK_CRYPTO_CAPABLE: capable of hardware encryption
*/
enum memblock_flags {
MEMBLOCK_NONE = 0x0, /* No special request */
@@ -47,6 +48,7 @@ enum memblock_flags {
MEMBLOCK_MIRROR = 0x2, /* mirrored region */
MEMBLOCK_NOMAP = 0x4, /* don't add to kernel direct mapping */
MEMBLOCK_DRIVER_MANAGED = 0x8, /* always detected via a driver */
+ MEMBLOCK_CRYPTO_CAPABLE = 0x10, /* capable of hardware encryption */
};
/**
@@ -120,6 +122,9 @@ int memblock_physmem_add(phys_addr_t base, phys_addr_t size);
void memblock_trim_memory(phys_addr_t align);
bool memblock_overlaps_region(struct memblock_type *type,
phys_addr_t base, phys_addr_t size);
+bool memblock_node_is_crypto_capable(int nid);
+int memblock_mark_crypto_capable(phys_addr_t base, phys_addr_t size);
+int memblock_clear_crypto_capable(phys_addr_t base, phys_addr_t size);
int memblock_mark_hotplug(phys_addr_t base, phys_addr_t size);
int memblock_clear_hotplug(phys_addr_t base, phys_addr_t size);
int memblock_mark_mirror(phys_addr_t base, phys_addr_t size);
diff --git a/mm/memblock.c b/mm/memblock.c
index e4f03a6e8e56..fe62f81572e6 100644
--- a/mm/memblock.c
+++ b/mm/memblock.c
@@ -191,6 +191,40 @@ bool __init_memblock memblock_overlaps_region(struct memblock_type *type,
return i < type->cnt;
}
+/**
+ * memblock_node_is_crypto_capable - get if whole node is capable
+ * of encryption
+ * @nid: number of node
+ *
+ * Iterate over all memory memblock_type and find if all regions under
+ * node @nid are capable of hardware encryption.
+ *
+ * Return:
+ * true if every region in memory memblock_type is capable of
+ * encryption, false otherwise.
+ */
+bool __init_memblock memblock_node_is_crypto_capable(int nid)
+{
+ struct memblock_region *region;
+ int crypto_capables = 0;
+ int not_crypto_capables = 0;
+
+ for_each_mem_region(region) {
+ if (memblock_get_region_node(region) == nid) {
+ if (region->flags & MEMBLOCK_CRYPTO_CAPABLE)
+ crypto_capables++;
+ else
+ not_crypto_capables++;
+ }
+ }
+
+ if (crypto_capables > 0 && not_crypto_capables > 0)
+ pr_warn("Node %d has %d regions that are encryptable and %d regions that aren't",
+ nid, not_crypto_capables, crypto_capables);
+
+ return not_crypto_capables == 0;
+}
+
/**
* __memblock_find_range_bottom_up - find free area utility in bottom-up
* @start: start of candidate range
@@ -891,6 +925,34 @@ static int __init_memblock memblock_setclr_flag(phys_addr_t base,
return 0;
}
+/**
+ * memblock_mark_crypto_capable - Mark memory regions capable of hardware
+ * encryption with flag MEMBLOCK_CRYPTO_CAPABLE.
+ * @base: the base phys addr of the region
+ * @size: the size of the region
+ *
+ * Return: 0 on success, -errno on failure.
+ */
+int __init_memblock memblock_mark_crypto_capable(phys_addr_t base,
+ phys_addr_t size)
+{
+ return memblock_setclr_flag(base, size, 1, MEMBLOCK_CRYPTO_CAPABLE);
+}
+
+/**
+ * memblock_clear_crypto_capable - Clear flag MEMBLOCK_CRYPTO for a
+ * specified region.
+ * @base: the base phys addr of the region
+ * @size: the size of the region
+ *
+ * Return: 0 on success, -errno on failure.
+ */
+int __init_memblock memblock_clear_crypto_capable(phys_addr_t base,
+ phys_addr_t size)
+{
+ return memblock_setclr_flag(base, size, 0, MEMBLOCK_CRYPTO_CAPABLE);
+}
+
/**
* memblock_mark_hotplug - Mark hotpluggable memory with flag MEMBLOCK_HOTPLUG.
* @base: the base phys addr of the region
--
2.30.2
On Mon, Apr 25, 2022 at 02:15:19PM -0300, Martin Fernandez wrote:
> Add the capability to mark regions of the memory memory_type able of
> hardware memory encryption.
>
> Also add the capability to query if all regions of a memory node are
> able to do hardware memory encryption to call it when initializing the
> nodes. Warn the user if a node has both encryptable and
> non-encryptable regions.
>
> Signed-off-by: Martin Fernandez <[email protected]>
> ---
> include/linux/memblock.h | 5 ++++
> mm/memblock.c | 62 ++++++++++++++++++++++++++++++++++++++++
> 2 files changed, 67 insertions(+)
>
> diff --git a/include/linux/memblock.h b/include/linux/memblock.h
> index 50ad19662a32..00c4f1a20335 100644
> --- a/include/linux/memblock.h
> +++ b/include/linux/memblock.h
> @@ -40,6 +40,7 @@ extern unsigned long long max_possible_pfn;
> * via a driver, and never indicated in the firmware-provided memory map as
> * system RAM. This corresponds to IORESOURCE_SYSRAM_DRIVER_MANAGED in the
> * kernel resource tree.
> + * @MEMBLOCK_CRYPTO_CAPABLE: capable of hardware encryption
> */
> enum memblock_flags {
> MEMBLOCK_NONE = 0x0, /* No special request */
> @@ -47,6 +48,7 @@ enum memblock_flags {
> MEMBLOCK_MIRROR = 0x2, /* mirrored region */
> MEMBLOCK_NOMAP = 0x4, /* don't add to kernel direct mapping */
> MEMBLOCK_DRIVER_MANAGED = 0x8, /* always detected via a driver */
> + MEMBLOCK_CRYPTO_CAPABLE = 0x10, /* capable of hardware encryption */
> };
>
> /**
> @@ -120,6 +122,9 @@ int memblock_physmem_add(phys_addr_t base, phys_addr_t size);
> void memblock_trim_memory(phys_addr_t align);
> bool memblock_overlaps_region(struct memblock_type *type,
> phys_addr_t base, phys_addr_t size);
> +bool memblock_node_is_crypto_capable(int nid);
> +int memblock_mark_crypto_capable(phys_addr_t base, phys_addr_t size);
> +int memblock_clear_crypto_capable(phys_addr_t base, phys_addr_t size);
> int memblock_mark_hotplug(phys_addr_t base, phys_addr_t size);
> int memblock_clear_hotplug(phys_addr_t base, phys_addr_t size);
> int memblock_mark_mirror(phys_addr_t base, phys_addr_t size);
> diff --git a/mm/memblock.c b/mm/memblock.c
> index e4f03a6e8e56..fe62f81572e6 100644
> --- a/mm/memblock.c
> +++ b/mm/memblock.c
> @@ -191,6 +191,40 @@ bool __init_memblock memblock_overlaps_region(struct memblock_type *type,
> return i < type->cnt;
> }
>
> +/**
> + * memblock_node_is_crypto_capable - get if whole node is capable
> + * of encryption
> + * @nid: number of node
> + *
> + * Iterate over all memory memblock_type and find if all regions under
> + * node @nid are capable of hardware encryption.
> + *
> + * Return:
> + * true if every region in memory memblock_type is capable of
I'd s/in memory memblock_type/in @nid
> + * encryption, false otherwise.
> + */
> +bool __init_memblock memblock_node_is_crypto_capable(int nid)
> +{
> + struct memblock_region *region;
> + int crypto_capables = 0;
> + int not_crypto_capables = 0;
> +
> + for_each_mem_region(region) {
> + if (memblock_get_region_node(region) == nid) {
> + if (region->flags & MEMBLOCK_CRYPTO_CAPABLE)
> + crypto_capables++;
> + else
> + not_crypto_capables++;
> + }
> + }
> +
> + if (crypto_capables > 0 && not_crypto_capables > 0)
> + pr_warn("Node %d has %d regions that are encryptable and %d regions that aren't",
> + nid, not_crypto_capables, crypto_capables);
> +
> + return not_crypto_capables == 0;
This will return true for memoryless nodes as well. Do you mean to consider
them as capable of encryption?
> +}
> +
> /**
> * __memblock_find_range_bottom_up - find free area utility in bottom-up
> * @start: start of candidate range
> @@ -891,6 +925,34 @@ static int __init_memblock memblock_setclr_flag(phys_addr_t base,
> return 0;
> }
>
> +/**
> + * memblock_mark_crypto_capable - Mark memory regions capable of hardware
> + * encryption with flag MEMBLOCK_CRYPTO_CAPABLE.
> + * @base: the base phys addr of the region
> + * @size: the size of the region
> + *
> + * Return: 0 on success, -errno on failure.
> + */
> +int __init_memblock memblock_mark_crypto_capable(phys_addr_t base,
> + phys_addr_t size)
> +{
> + return memblock_setclr_flag(base, size, 1, MEMBLOCK_CRYPTO_CAPABLE);
> +}
> +
> +/**
> + * memblock_clear_crypto_capable - Clear flag MEMBLOCK_CRYPTO for a
> + * specified region.
> + * @base: the base phys addr of the region
> + * @size: the size of the region
> + *
> + * Return: 0 on success, -errno on failure.
> + */
> +int __init_memblock memblock_clear_crypto_capable(phys_addr_t base,
> + phys_addr_t size)
> +{
> + return memblock_setclr_flag(base, size, 0, MEMBLOCK_CRYPTO_CAPABLE);
> +}
> +
> /**
> * memblock_mark_hotplug - Mark hotpluggable memory with flag MEMBLOCK_HOTPLUG.
> * @base: the base phys addr of the region
> --
> 2.30.2
>
--
Sincerely yours,
Mike.
On Tue, Apr 26, 2022 at 09:59:04AM -0300, Martin Fernandez wrote:
> On 4/26/22, Mike Rapoport <[email protected]> wrote:
> > On Mon, Apr 25, 2022 at 02:15:19PM -0300, Martin Fernandez wrote:
> >> Add the capability to mark regions of the memory memory_type able of
> >> hardware memory encryption.
> >>
> >> Also add the capability to query if all regions of a memory node are
> >> able to do hardware memory encryption to call it when initializing the
> >> nodes. Warn the user if a node has both encryptable and
> >> non-encryptable regions.
> >>
> >> Signed-off-by: Martin Fernandez <[email protected]>
> >> ---
> >> include/linux/memblock.h | 5 ++++
> >> mm/memblock.c | 62 ++++++++++++++++++++++++++++++++++++++++
> >> 2 files changed, 67 insertions(+)
> >>
> >> diff --git a/include/linux/memblock.h b/include/linux/memblock.h
> >> index 50ad19662a32..00c4f1a20335 100644
> >> --- a/include/linux/memblock.h
> >> +++ b/include/linux/memblock.h
> >> @@ -40,6 +40,7 @@ extern unsigned long long max_possible_pfn;
> >> * via a driver, and never indicated in the firmware-provided memory map
> >> as
> >> * system RAM. This corresponds to IORESOURCE_SYSRAM_DRIVER_MANAGED in
> >> the
> >> * kernel resource tree.
> >> + * @MEMBLOCK_CRYPTO_CAPABLE: capable of hardware encryption
> >> */
> >> enum memblock_flags {
> >> MEMBLOCK_NONE = 0x0, /* No special request */
> >> @@ -47,6 +48,7 @@ enum memblock_flags {
> >> MEMBLOCK_MIRROR = 0x2, /* mirrored region */
> >> MEMBLOCK_NOMAP = 0x4, /* don't add to kernel direct mapping */
> >> MEMBLOCK_DRIVER_MANAGED = 0x8, /* always detected via a driver */
> >> + MEMBLOCK_CRYPTO_CAPABLE = 0x10, /* capable of hardware encryption */
> >> };
> >>
> >> /**
> >> @@ -120,6 +122,9 @@ int memblock_physmem_add(phys_addr_t base, phys_addr_t
> >> size);
> >> void memblock_trim_memory(phys_addr_t align);
> >> bool memblock_overlaps_region(struct memblock_type *type,
> >> phys_addr_t base, phys_addr_t size);
> >> +bool memblock_node_is_crypto_capable(int nid);
> >> +int memblock_mark_crypto_capable(phys_addr_t base, phys_addr_t size);
> >> +int memblock_clear_crypto_capable(phys_addr_t base, phys_addr_t size);
> >> int memblock_mark_hotplug(phys_addr_t base, phys_addr_t size);
> >> int memblock_clear_hotplug(phys_addr_t base, phys_addr_t size);
> >> int memblock_mark_mirror(phys_addr_t base, phys_addr_t size);
> >> diff --git a/mm/memblock.c b/mm/memblock.c
> >> index e4f03a6e8e56..fe62f81572e6 100644
> >> --- a/mm/memblock.c
> >> +++ b/mm/memblock.c
> >> @@ -191,6 +191,40 @@ bool __init_memblock memblock_overlaps_region(struct
> >> memblock_type *type,
> >> return i < type->cnt;
> >> }
> >>
> >> +/**
> >> + * memblock_node_is_crypto_capable - get if whole node is capable
> >> + * of encryption
> >> + * @nid: number of node
> >> + *
> >> + * Iterate over all memory memblock_type and find if all regions under
> >> + * node @nid are capable of hardware encryption.
> >> + *
> >> + * Return:
> >> + * true if every region in memory memblock_type is capable of
> >
> > I'd s/in memory memblock_type/in @nid
> >
>
> Good, thanks.
>
> >> + * encryption, false otherwise.
> >> + */
> >> +bool __init_memblock memblock_node_is_crypto_capable(int nid)
> >> +{
> >> + struct memblock_region *region;
> >> + int crypto_capables = 0;
> >> + int not_crypto_capables = 0;
> >> +
> >> + for_each_mem_region(region) {
> >> + if (memblock_get_region_node(region) == nid) {
> >> + if (region->flags & MEMBLOCK_CRYPTO_CAPABLE)
> >> + crypto_capables++;
> >> + else
> >> + not_crypto_capables++;
> >> + }
> >> + }
> >> +
> >> + if (crypto_capables > 0 && not_crypto_capables > 0)
> >> + pr_warn("Node %d has %d regions that are encryptable and %d regions
> >> that aren't",
> >> + nid, not_crypto_capables, crypto_capables);
> >> +
> >> + return not_crypto_capables == 0;
> >
> > This will return true for memoryless nodes as well. Do you mean to consider
> > them as capable of encryption?
> >
>
> Not really, I didn't think about that to be honest. I don't think it's
> a good idea to consider them as capable, right?
I think capable of encryption would mean
crypto_capables && !not_crypto_capables
--
Sincerely yours,
Mike.
On 4/26/22, Mike Rapoport <[email protected]> wrote:
> On Mon, Apr 25, 2022 at 02:15:19PM -0300, Martin Fernandez wrote:
>> Add the capability to mark regions of the memory memory_type able of
>> hardware memory encryption.
>>
>> Also add the capability to query if all regions of a memory node are
>> able to do hardware memory encryption to call it when initializing the
>> nodes. Warn the user if a node has both encryptable and
>> non-encryptable regions.
>>
>> Signed-off-by: Martin Fernandez <[email protected]>
>> ---
>> include/linux/memblock.h | 5 ++++
>> mm/memblock.c | 62 ++++++++++++++++++++++++++++++++++++++++
>> 2 files changed, 67 insertions(+)
>>
>> diff --git a/include/linux/memblock.h b/include/linux/memblock.h
>> index 50ad19662a32..00c4f1a20335 100644
>> --- a/include/linux/memblock.h
>> +++ b/include/linux/memblock.h
>> @@ -40,6 +40,7 @@ extern unsigned long long max_possible_pfn;
>> * via a driver, and never indicated in the firmware-provided memory map
>> as
>> * system RAM. This corresponds to IORESOURCE_SYSRAM_DRIVER_MANAGED in
>> the
>> * kernel resource tree.
>> + * @MEMBLOCK_CRYPTO_CAPABLE: capable of hardware encryption
>> */
>> enum memblock_flags {
>> MEMBLOCK_NONE = 0x0, /* No special request */
>> @@ -47,6 +48,7 @@ enum memblock_flags {
>> MEMBLOCK_MIRROR = 0x2, /* mirrored region */
>> MEMBLOCK_NOMAP = 0x4, /* don't add to kernel direct mapping */
>> MEMBLOCK_DRIVER_MANAGED = 0x8, /* always detected via a driver */
>> + MEMBLOCK_CRYPTO_CAPABLE = 0x10, /* capable of hardware encryption */
>> };
>>
>> /**
>> @@ -120,6 +122,9 @@ int memblock_physmem_add(phys_addr_t base, phys_addr_t
>> size);
>> void memblock_trim_memory(phys_addr_t align);
>> bool memblock_overlaps_region(struct memblock_type *type,
>> phys_addr_t base, phys_addr_t size);
>> +bool memblock_node_is_crypto_capable(int nid);
>> +int memblock_mark_crypto_capable(phys_addr_t base, phys_addr_t size);
>> +int memblock_clear_crypto_capable(phys_addr_t base, phys_addr_t size);
>> int memblock_mark_hotplug(phys_addr_t base, phys_addr_t size);
>> int memblock_clear_hotplug(phys_addr_t base, phys_addr_t size);
>> int memblock_mark_mirror(phys_addr_t base, phys_addr_t size);
>> diff --git a/mm/memblock.c b/mm/memblock.c
>> index e4f03a6e8e56..fe62f81572e6 100644
>> --- a/mm/memblock.c
>> +++ b/mm/memblock.c
>> @@ -191,6 +191,40 @@ bool __init_memblock memblock_overlaps_region(struct
>> memblock_type *type,
>> return i < type->cnt;
>> }
>>
>> +/**
>> + * memblock_node_is_crypto_capable - get if whole node is capable
>> + * of encryption
>> + * @nid: number of node
>> + *
>> + * Iterate over all memory memblock_type and find if all regions under
>> + * node @nid are capable of hardware encryption.
>> + *
>> + * Return:
>> + * true if every region in memory memblock_type is capable of
>
> I'd s/in memory memblock_type/in @nid
>
Good, thanks.
>> + * encryption, false otherwise.
>> + */
>> +bool __init_memblock memblock_node_is_crypto_capable(int nid)
>> +{
>> + struct memblock_region *region;
>> + int crypto_capables = 0;
>> + int not_crypto_capables = 0;
>> +
>> + for_each_mem_region(region) {
>> + if (memblock_get_region_node(region) == nid) {
>> + if (region->flags & MEMBLOCK_CRYPTO_CAPABLE)
>> + crypto_capables++;
>> + else
>> + not_crypto_capables++;
>> + }
>> + }
>> +
>> + if (crypto_capables > 0 && not_crypto_capables > 0)
>> + pr_warn("Node %d has %d regions that are encryptable and %d regions
>> that aren't",
>> + nid, not_crypto_capables, crypto_capables);
>> +
>> + return not_crypto_capables == 0;
>
> This will return true for memoryless nodes as well. Do you mean to consider
> them as capable of encryption?
>
Not really, I didn't think about that to be honest. I don't think it's
a good idea to consider them as capable, right?
On Tue, Apr 26, 2022 at 10:21 AM Mike Rapoport <[email protected]> wrote:
>
> On Tue, Apr 26, 2022 at 09:59:04AM -0300, Martin Fernandez wrote:
> > On 4/26/22, Mike Rapoport <[email protected]> wrote:
> > > On Mon, Apr 25, 2022 at 02:15:19PM -0300, Martin Fernandez wrote:
> > >> Add the capability to mark regions of the memory memory_type able of
> > >> hardware memory encryption.
> > >>
> > >> Also add the capability to query if all regions of a memory node are
> > >> able to do hardware memory encryption to call it when initializing the
> > >> nodes. Warn the user if a node has both encryptable and
> > >> non-encryptable regions.
> > >>
> > >> Signed-off-by: Martin Fernandez <[email protected]>
> > >> ---
> > >> include/linux/memblock.h | 5 ++++
> > >> mm/memblock.c | 62 ++++++++++++++++++++++++++++++++++++++++
> > >> 2 files changed, 67 insertions(+)
> > >>
> > >> diff --git a/include/linux/memblock.h b/include/linux/memblock.h
> > >> index 50ad19662a32..00c4f1a20335 100644
> > >> --- a/include/linux/memblock.h
> > >> +++ b/include/linux/memblock.h
> > >> @@ -40,6 +40,7 @@ extern unsigned long long max_possible_pfn;
> > >> * via a driver, and never indicated in the firmware-provided memory map
> > >> as
> > >> * system RAM. This corresponds to IORESOURCE_SYSRAM_DRIVER_MANAGED in
> > >> the
> > >> * kernel resource tree.
> > >> + * @MEMBLOCK_CRYPTO_CAPABLE: capable of hardware encryption
> > >> */
> > >> enum memblock_flags {
> > >> MEMBLOCK_NONE = 0x0, /* No special request */
> > >> @@ -47,6 +48,7 @@ enum memblock_flags {
> > >> MEMBLOCK_MIRROR = 0x2, /* mirrored region */
> > >> MEMBLOCK_NOMAP = 0x4, /* don't add to kernel direct mapping */
> > >> MEMBLOCK_DRIVER_MANAGED = 0x8, /* always detected via a driver */
> > >> + MEMBLOCK_CRYPTO_CAPABLE = 0x10, /* capable of hardware encryption */
> > >> };
> > >>
> > >> /**
> > >> @@ -120,6 +122,9 @@ int memblock_physmem_add(phys_addr_t base, phys_addr_t
> > >> size);
> > >> void memblock_trim_memory(phys_addr_t align);
> > >> bool memblock_overlaps_region(struct memblock_type *type,
> > >> phys_addr_t base, phys_addr_t size);
> > >> +bool memblock_node_is_crypto_capable(int nid);
> > >> +int memblock_mark_crypto_capable(phys_addr_t base, phys_addr_t size);
> > >> +int memblock_clear_crypto_capable(phys_addr_t base, phys_addr_t size);
> > >> int memblock_mark_hotplug(phys_addr_t base, phys_addr_t size);
> > >> int memblock_clear_hotplug(phys_addr_t base, phys_addr_t size);
> > >> int memblock_mark_mirror(phys_addr_t base, phys_addr_t size);
> > >> diff --git a/mm/memblock.c b/mm/memblock.c
> > >> index e4f03a6e8e56..fe62f81572e6 100644
> > >> --- a/mm/memblock.c
> > >> +++ b/mm/memblock.c
> > >> @@ -191,6 +191,40 @@ bool __init_memblock memblock_overlaps_region(struct
> > >> memblock_type *type,
> > >> return i < type->cnt;
> > >> }
> > >>
> > >> +/**
> > >> + * memblock_node_is_crypto_capable - get if whole node is capable
> > >> + * of encryption
> > >> + * @nid: number of node
> > >> + *
> > >> + * Iterate over all memory memblock_type and find if all regions under
> > >> + * node @nid are capable of hardware encryption.
> > >> + *
> > >> + * Return:
> > >> + * true if every region in memory memblock_type is capable of
> > >
> > > I'd s/in memory memblock_type/in @nid
> > >
> >
> > Good, thanks.
> >
> > >> + * encryption, false otherwise.
> > >> + */
> > >> +bool __init_memblock memblock_node_is_crypto_capable(int nid)
> > >> +{
> > >> + struct memblock_region *region;
> > >> + int crypto_capables = 0;
> > >> + int not_crypto_capables = 0;
> > >> +
> > >> + for_each_mem_region(region) {
> > >> + if (memblock_get_region_node(region) == nid) {
> > >> + if (region->flags & MEMBLOCK_CRYPTO_CAPABLE)
> > >> + crypto_capables++;
> > >> + else
> > >> + not_crypto_capables++;
> > >> + }
> > >> + }
> > >> +
> > >> + if (crypto_capables > 0 && not_crypto_capables > 0)
> > >> + pr_warn("Node %d has %d regions that are encryptable and %d regions
> > >> that aren't",
> > >> + nid, not_crypto_capables, crypto_capables);
> > >> +
> > >> + return not_crypto_capables == 0;
> > >
> > > This will return true for memoryless nodes as well. Do you mean to consider
> > > them as capable of encryption?
> > >
> >
> > Not really, I didn't think about that to be honest. I don't think it's
> > a good idea to consider them as capable, right?
>
> I think capable of encryption would mean
>
> crypto_capables && !not_crypto_capables
Since these operands were evaluated above with comparison ops, I would say
crypto_capables > 0 && not_crypto_capables == 0
to improve readability and be explicit that they are numbers rather
than booleans.
>
> --
> Sincerely yours,
> Mike.