It is not node 0, it is whatever node the kernel resides in. Tang Chen <[email protected]> wrote:
>When using movablemem_map=acpi, always set node0 as unhotpluggable, >otherwise >if all the memory is hotpluggable, the kernel will fail to boot. > >When using movablemem_map=nn[KMG]@ss[KMG], we don't stop users >specifying >node0 as hotpluggable, and ignore all the info in SRAT, so that this >option >can be used as a workaround of firmware bugs. > >Reported-by: H. Peter Anvin <[email protected]> >Signed-off-by: Tang Chen <[email protected]> >--- > Documentation/kernel-parameters.txt | 6 ++++++ > arch/x86/mm/srat.c | 10 ++++++++-- > 2 files changed, 14 insertions(+), 2 deletions(-) > >diff --git a/Documentation/kernel-parameters.txt >b/Documentation/kernel-parameters.txt >index 7d1b6fc..81b6f15 100644 >--- a/Documentation/kernel-parameters.txt >+++ b/Documentation/kernel-parameters.txt >@@ -1645,6 +1645,8 @@ bytes respectively. Such letter suffixes can also >be entirely omitted. > in flags from SRAT from ACPI BIOS to determine which > memory devices could be hotplugged. The corresponding > memory ranges will be set as ZONE_MOVABLE. >+ NOTE: node0 should always be unhotpluggable, otherwise >+ the kernel will fail to boot. > > movablemem_map=nn[KMG]@ss[KMG] > [KNL,X86,IA-64,PPC] This parameter is similar to >@@ -1666,6 +1668,10 @@ bytes respectively. Such letter suffixes can >also be entirely omitted. > satisfied. So the administrator should be careful that > the amount of movablemem_map areas are not too large. > Otherwise kernel won't have enough memory to start. >+ NOTE: We don't stop users specifying node0 as >+ hotpluggable, and ingore all the info in SRAT so >+ that this option can be used as a workaround of >+ firmware bugs. > > MTD_Partition= [MTD] > Format: <name>,<region-number>,<size>,<offset> >diff --git a/arch/x86/mm/srat.c b/arch/x86/mm/srat.c >index b20b5b7..a85d2b7 100644 >--- a/arch/x86/mm/srat.c >+++ b/arch/x86/mm/srat.c >@@ -161,9 +161,13 @@ handle_movablemem(int node, u64 start, u64 end, >u32 hotpluggable) > * > * Using movablemem_map, we can prevent memblock from allocating >memory > * on ZONE_MOVABLE at boot time. >+ * >+ * NOTE: node0 shoule always be unhotpluggable, otherwise, if all the >+ * memory is hotpluggable, there will be no memory kernel can >use. > */ > if (hotpluggable && movablemem_map.acpi) { >- insert_movablemem_map(start_pfn, end_pfn); >+ if (node != 0) >+ insert_movablemem_map(start_pfn, end_pfn); > goto out; > } > >@@ -178,7 +182,9 @@ handle_movablemem(int node, u64 start, u64 end, u32 >hotpluggable) > * Using movablemem_map, we can prevent memblock from allocating >memory > * on ZONE_MOVABLE at boot time. > * >- * NOTE: In this case, SRAT info will be ingored. >+ * NOTE: We don't stop users specifying node0 as hotpluggable, and >+ * ignore all the info in SRAT, so that this option can be used >+ * as a workaround of firmware bugs. > */ > overlap = movablemem_map_overlap(start_pfn, end_pfn); > if (overlap >= 0) { -- Sent from my mobile phone. Please excuse brevity and lack of formatting. -- To unsubscribe from this list: send the line "unsubscribe linux-kernel" in the body of a message to [email protected] More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/
