6.6-stable review patch. If anyone has any objections, please let me know.
------------------
From: Heiko Carstens hca@linux.ibm.com
commit 1954da4a2b621a3328a63382cae7e5f5e2af502c upstream.
If the cmma no-dat feature is available all pages that are not used for dynamic address translation are marked as "no-dat" with the ESSA instruction. This information is visible to the hypervisor, so that the hypervisor can optimize purging of guest TLB entries. This also means that pages which are used for dynamic address translation must not be marked as "no-dat", since the hypervisor may then incorrectly not purge guest TLB entries.
Region, segment, and page tables allocated within the gmap code are incorrectly marked as "no-dat", since an explicit call to arch_set_page_dat() is missing, which would remove the "no-dat" mark.
In order to fix this add a new gmap_alloc_crst() function which should be used to allocate region and segment tables, and which also calls arch_set_page_dat().
Also add the arch_set_page_dat() call to page_table_alloc_pgste().
Cc: stable@vger.kernel.org Reviewed-by: Claudio Imbrenda imbrenda@linux.ibm.com Signed-off-by: Heiko Carstens hca@linux.ibm.com Signed-off-by: Vasily Gorbik gor@linux.ibm.com Signed-off-by: Greg Kroah-Hartman gregkh@linuxfoundation.org --- arch/s390/mm/gmap.c | 24 ++++++++++++++++++------ arch/s390/mm/pgalloc.c | 1 + 2 files changed, 19 insertions(+), 6 deletions(-)
--- a/arch/s390/mm/gmap.c +++ b/arch/s390/mm/gmap.c @@ -21,10 +21,22 @@
#include <asm/pgalloc.h> #include <asm/gmap.h> +#include <asm/page.h> #include <asm/tlb.h>
#define GMAP_SHADOW_FAKE_TABLE 1ULL
+static struct page *gmap_alloc_crst(void) +{ + struct page *page; + + page = alloc_pages(GFP_KERNEL_ACCOUNT, CRST_ALLOC_ORDER); + if (!page) + return NULL; + arch_set_page_dat(page, CRST_ALLOC_ORDER); + return page; +} + /** * gmap_alloc - allocate and initialize a guest address space * @limit: maximum address of the gmap address space @@ -67,7 +79,7 @@ static struct gmap *gmap_alloc(unsigned spin_lock_init(&gmap->guest_table_lock); spin_lock_init(&gmap->shadow_lock); refcount_set(&gmap->ref_count, 1); - page = alloc_pages(GFP_KERNEL_ACCOUNT, CRST_ALLOC_ORDER); + page = gmap_alloc_crst(); if (!page) goto out_free; page->index = 0; @@ -308,7 +320,7 @@ static int gmap_alloc_table(struct gmap unsigned long *new;
/* since we dont free the gmap table until gmap_free we can unlock */ - page = alloc_pages(GFP_KERNEL_ACCOUNT, CRST_ALLOC_ORDER); + page = gmap_alloc_crst(); if (!page) return -ENOMEM; new = page_to_virt(page); @@ -1759,7 +1771,7 @@ int gmap_shadow_r2t(struct gmap *sg, uns
BUG_ON(!gmap_is_shadow(sg)); /* Allocate a shadow region second table */ - page = alloc_pages(GFP_KERNEL_ACCOUNT, CRST_ALLOC_ORDER); + page = gmap_alloc_crst(); if (!page) return -ENOMEM; page->index = r2t & _REGION_ENTRY_ORIGIN; @@ -1843,7 +1855,7 @@ int gmap_shadow_r3t(struct gmap *sg, uns
BUG_ON(!gmap_is_shadow(sg)); /* Allocate a shadow region second table */ - page = alloc_pages(GFP_KERNEL_ACCOUNT, CRST_ALLOC_ORDER); + page = gmap_alloc_crst(); if (!page) return -ENOMEM; page->index = r3t & _REGION_ENTRY_ORIGIN; @@ -1927,7 +1939,7 @@ int gmap_shadow_sgt(struct gmap *sg, uns
BUG_ON(!gmap_is_shadow(sg) || (sgt & _REGION3_ENTRY_LARGE)); /* Allocate a shadow segment table */ - page = alloc_pages(GFP_KERNEL_ACCOUNT, CRST_ALLOC_ORDER); + page = gmap_alloc_crst(); if (!page) return -ENOMEM; page->index = sgt & _REGION_ENTRY_ORIGIN; @@ -2855,7 +2867,7 @@ int s390_replace_asce(struct gmap *gmap) if ((gmap->asce & _ASCE_TYPE_MASK) == _ASCE_TYPE_SEGMENT) return -EINVAL;
- page = alloc_pages(GFP_KERNEL_ACCOUNT, CRST_ALLOC_ORDER); + page = gmap_alloc_crst(); if (!page) return -ENOMEM; page->index = 0; --- a/arch/s390/mm/pgalloc.c +++ b/arch/s390/mm/pgalloc.c @@ -146,6 +146,7 @@ struct page *page_table_alloc_pgste(stru ptdesc = pagetable_alloc(GFP_KERNEL, 0); if (ptdesc) { table = (u64 *)ptdesc_to_virt(ptdesc); + arch_set_page_dat(virt_to_page(table), 0); memset64(table, _PAGE_INVALID, PTRS_PER_PTE); memset64(table + PTRS_PER_PTE, 0, PTRS_PER_PTE); }