diff options
| author | Michael Ellerman | 2022-06-16 18:41:49 +1000 |
|---|---|---|
| committer | Michael Ellerman | 2022-06-18 10:18:55 +1000 |
| commit | 6cf06c17e94f26c290fd3370a5c36514ae15ac43 (patch) | |
| tree | 0d986314d00bc9cd7194356c1b91126fc3ac5cf8 /arch/powerpc | |
| parent | b13baccc3850ca8b8cccbf8ed9912dbaa0fdf7f3 (diff) | |
powerpc/mm: Move CMA reservations after initmem_init()
After commit 11ac3e87ce09 ("mm: cma: use pageblock_order as the single
alignment") there is an error at boot about the KVM CMA reservation
failing, eg:
kvm_cma_reserve: reserving 6553 MiB for global area
cma: Failed to reserve 6553 MiB
That makes it impossible to start KVM guests using the hash MMU with
more than 2G of memory, because the VM is unable to allocate a large
enough region for the hash page table, eg:
$ qemu-system-ppc64 -enable-kvm -M pseries -m 4G ...
qemu-system-ppc64: Failed to allocate KVM HPT of order 25: Cannot allocate memory
Aneesh pointed out that this happens because when kvm_cma_reserve() is
called, pageblock_order has not been initialised yet, and is still zero,
causing the checks in cma_init_reserved_mem() against
CMA_MIN_ALIGNMENT_PAGES to fail.
Fix it by moving the call to kvm_cma_reserve() after initmem_init(). The
pageblock_order is initialised in sparse_init() which is called from
initmem_init().
Also move the hugetlb CMA reservation.
Fixes: 11ac3e87ce09 ("mm: cma: use pageblock_order as the single alignment")
Reviewed-by: Aneesh Kumar K.V <aneesh.kumar@linux.ibm.com>
Reviewed-by: Zi Yan <ziy@nvidia.com>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
Link: https://lore.kernel.org/r/20220616120033.1976732-1-mpe@ellerman.id.au
Diffstat (limited to 'arch/powerpc')
| -rw-r--r-- | arch/powerpc/kernel/setup-common.c | 13 |
1 files changed, 7 insertions, 6 deletions
diff --git a/arch/powerpc/kernel/setup-common.c b/arch/powerpc/kernel/setup-common.c index eb0077b302e2..1a02629ec70b 100644 --- a/arch/powerpc/kernel/setup-common.c +++ b/arch/powerpc/kernel/setup-common.c @@ -935,12 +935,6 @@ void __init setup_arch(char **cmdline_p) /* Print various info about the machine that has been gathered so far. */ print_system_info(); - /* Reserve large chunks of memory for use by CMA for KVM. */ - kvm_cma_reserve(); - - /* Reserve large chunks of memory for us by CMA for hugetlb */ - gigantic_hugetlb_cma_reserve(); - klp_init_thread_info(&init_task); setup_initial_init_mm(_stext, _etext, _edata, _end); @@ -955,6 +949,13 @@ void __init setup_arch(char **cmdline_p) initmem_init(); + /* + * Reserve large chunks of memory for use by CMA for KVM and hugetlb. These must + * be called after initmem_init(), so that pageblock_order is initialised. + */ + kvm_cma_reserve(); + gigantic_hugetlb_cma_reserve(); + early_memtest(min_low_pfn << PAGE_SHIFT, max_low_pfn << PAGE_SHIFT); if (ppc_md.setup_arch) |