This is a note to let you know that I've just added the patch titled
s390/mm: add missing arch_set_page_dat() call to gmap allocations
to the 6.6-stable tree which can be found at:
http://www.kernel.org/git/?p=linux/kernel/git/stable/stable-queue.git;a=summary
The filename of the patch is:
s390-mm-add-missing-arch_set_page_dat-call-to-gmap-allocations.patch
and it can be found in the queue-6.6 subdirectory.
If you, or anyone else, feels it should not be added to the stable tree,
please let <stable@xxxxxxxxxxxxxxx> know about it.
>From 1954da4a2b621a3328a63382cae7e5f5e2af502c Mon Sep 17 00:00:00 2001
From: Heiko Carstens <hca@xxxxxxxxxxxxx>
Date: Fri, 20 Oct 2023 17:26:50 +0200
Subject: s390/mm: add missing arch_set_page_dat() call to gmap allocations
From: Heiko Carstens <hca@xxxxxxxxxxxxx>
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@xxxxxxxxxxxxxxx>
Reviewed-by: Claudio Imbrenda <imbrenda@xxxxxxxxxxxxx>
Signed-off-by: Heiko Carstens <hca@xxxxxxxxxxxxx>
Signed-off-by: Vasily Gorbik <gor@xxxxxxxxxxxxx>
Signed-off-by: Greg Kroah-Hartman <gregkh@xxxxxxxxxxxxxxxxxxx>
---
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);
}
Patches currently in stable-queue which might be from hca@xxxxxxxxxxxxx are
queue-6.6/s390-mm-add-missing-arch_set_page_dat-call-to-vmem_crst_alloc.patch
queue-6.6/s390-cmma-fix-initial-kernel-address-space-page-table-walk.patch
queue-6.6/s390-cmma-fix-handling-of-swapper_pg_dir-and-invalid_pg_dir.patch
queue-6.6/s390-cmma-fix-detection-of-dat-pages.patch
queue-6.6/s390-mm-add-missing-arch_set_page_dat-call-to-gmap-allocations.patch
