From: Juergen Gross jgross@suse.com
Collapsing pages to a leaf PMD or PUD should be done only if X86_FEATURE_PSE is available, which is not the case when running e.g. as a Xen PV guest.
Cc: stable@vger.kernel.org Fixes: 41d88484c71c ("x86/mm/pat: restore large ROX pages after fragmentation") Signed-off-by: Juergen Gross jgross@suse.com Link: https://lore.kernel.org/r/20250528123557.12847-3-jgross@suse.com Signed-off-by: Mike Rapoport (Microsoft) rppt@kernel.org --- arch/x86/mm/pat/set_memory.c | 3 +++ 1 file changed, 3 insertions(+)
diff --git a/arch/x86/mm/pat/set_memory.c b/arch/x86/mm/pat/set_memory.c index def3d9284254..9292f835cf5a 100644 --- a/arch/x86/mm/pat/set_memory.c +++ b/arch/x86/mm/pat/set_memory.c @@ -1257,6 +1257,9 @@ static int collapse_pmd_page(pmd_t *pmd, unsigned long addr, pgprot_t pgprot; int i = 0;
+ if (!cpu_feature_enabled(X86_FEATURE_PSE)) + return 0; + addr &= PMD_MASK; pte = pte_offset_kernel(pmd, addr); first = *pte;