The patch titled
Subject: mm: remove vmalloc_sync_(un)mappings()
has been added to the -mm tree. Its filename is
mm-remove-vmalloc_sync_unmappings.patch
This patch should soon appear at
http://ozlabs.org/~akpm/mmots/broken-out/mm-remove-vmalloc_sync_unmappings.patch
and later at
http://ozlabs.org/~akpm/mmotm/broken-out/mm-remove-vmalloc_sync_unmappings.patch
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*** Remember to use Documentation/process/submit-checklist.rst when testing your code ***
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------------------------------------------------------
From: Joerg Roedel <jroedel@xxxxxxx>
Subject: mm: remove vmalloc_sync_(un)mappings()
These functions are not needed anymore because the vmalloc and ioremap
mappings are now synchronized when they are created or teared down.
Remove all callers and function definitions.
Link: http://lkml.kernel.org/r/20200515140023.25469-7-joro@xxxxxxxxxx
Signed-off-by: Joerg Roedel <jroedel@xxxxxxx>
Tested-by: Steven Rostedt (VMware) <rostedt@xxxxxxxxxxx>
Acked-by: Andy Lutomirski <luto@xxxxxxxxxx>
Acked-by: Peter Zijlstra (Intel) <peterz@xxxxxxxxxxxxx>
Cc: Arnd Bergmann <arnd@xxxxxxxx>
Cc: Christoph Hellwig <hch@xxxxxx>
Cc: Dave Hansen <dave.hansen@xxxxxxxxxxxxxxx>
Cc: "H . Peter Anvin" <hpa@xxxxxxxxx>
Cc: Ingo Molnar <mingo@xxxxxxx>
Cc: Matthew Wilcox (Oracle) <willy@xxxxxxxxxxxxx>
Cc: Michal Hocko <mhocko@xxxxxxxxxx>
Cc: "Rafael J. Wysocki" <rjw@xxxxxxxxxxxxx>
Cc: Thomas Gleixner <tglx@xxxxxxxxxxxxx>
Cc: Vlastimil Babka <vbabka@xxxxxxx>
Signed-off-by: Andrew Morton <akpm@xxxxxxxxxxxxxxxxxxxx>
---
arch/x86/mm/fault.c | 37 -------------------------------------
drivers/acpi/apei/ghes.c | 6 ------
include/linux/vmalloc.h | 2 --
kernel/notifier.c | 1 -
kernel/trace/trace.c | 12 ------------
mm/nommu.c | 12 ------------
mm/vmalloc.c | 21 ---------------------
7 files changed, 91 deletions(-)
--- a/arch/x86/mm/fault.c~mm-remove-vmalloc_sync_unmappings
+++ a/arch/x86/mm/fault.c
@@ -214,26 +214,6 @@ void arch_sync_kernel_mappings(unsigned
}
}
-static void vmalloc_sync(void)
-{
- unsigned long address;
-
- if (SHARED_KERNEL_PMD)
- return;
-
- arch_sync_kernel_mappings(VMALLOC_START, VMALLOC_END);
-}
-
-void vmalloc_sync_mappings(void)
-{
- vmalloc_sync();
-}
-
-void vmalloc_sync_unmappings(void)
-{
- vmalloc_sync();
-}
-
/*
* 32-bit:
*
@@ -336,23 +316,6 @@ out:
#else /* CONFIG_X86_64: */
-void vmalloc_sync_mappings(void)
-{
- /*
- * 64-bit mappings might allocate new p4d/pud pages
- * that need to be propagated to all tasks' PGDs.
- */
- sync_global_pgds(VMALLOC_START & PGDIR_MASK, VMALLOC_END);
-}
-
-void vmalloc_sync_unmappings(void)
-{
- /*
- * Unmappings never allocate or free p4d/pud pages.
- * No work is required here.
- */
-}
-
/*
* 64-bit:
*
--- a/drivers/acpi/apei/ghes.c~mm-remove-vmalloc_sync_unmappings
+++ a/drivers/acpi/apei/ghes.c
@@ -167,12 +167,6 @@ int ghes_estatus_pool_init(int num_ghes)
if (!addr)
goto err_pool_alloc;
- /*
- * New allocation must be visible in all pgd before it can be found by
- * an NMI allocating from the pool.
- */
- vmalloc_sync_mappings();
-
rc = gen_pool_add(ghes_estatus_pool, addr, PAGE_ALIGN(len), -1);
if (rc)
goto err_pool_add;
--- a/include/linux/vmalloc.h~mm-remove-vmalloc_sync_unmappings
+++ a/include/linux/vmalloc.h
@@ -130,8 +130,6 @@ extern int remap_vmalloc_range_partial(s
extern int remap_vmalloc_range(struct vm_area_struct *vma, void *addr,
unsigned long pgoff);
-void vmalloc_sync_mappings(void);
-void vmalloc_sync_unmappings(void);
/*
* Architectures can set this mask to a combination of PGTBL_P?D_MODIFIED values
--- a/kernel/notifier.c~mm-remove-vmalloc_sync_unmappings
+++ a/kernel/notifier.c
@@ -519,7 +519,6 @@ NOKPROBE_SYMBOL(notify_die);
int register_die_notifier(struct notifier_block *nb)
{
- vmalloc_sync_mappings();
return atomic_notifier_chain_register(&die_chain, nb);
}
EXPORT_SYMBOL_GPL(register_die_notifier);
--- a/kernel/trace/trace.c~mm-remove-vmalloc_sync_unmappings
+++ a/kernel/trace/trace.c
@@ -8527,18 +8527,6 @@ static int allocate_trace_buffers(struct
allocate_snapshot = false;
#endif
- /*
- * Because of some magic with the way alloc_percpu() works on
- * x86_64, we need to synchronize the pgd of all the tables,
- * otherwise the trace events that happen in x86_64 page fault
- * handlers can't cope with accessing the chance that a
- * alloc_percpu()'d memory might be touched in the page fault trace
- * event. Oh, and we need to audit all other alloc_percpu() and vmalloc()
- * calls in tracing, because something might get triggered within a
- * page fault trace event!
- */
- vmalloc_sync_mappings();
-
return 0;
}
--- a/mm/nommu.c~mm-remove-vmalloc_sync_unmappings
+++ a/mm/nommu.c
@@ -371,18 +371,6 @@ void vm_unmap_aliases(void)
}
EXPORT_SYMBOL_GPL(vm_unmap_aliases);
-/*
- * Implement a stub for vmalloc_sync_[un]mapping() if the architecture
- * chose not to have one.
- */
-void __weak vmalloc_sync_mappings(void)
-{
-}
-
-void __weak vmalloc_sync_unmappings(void)
-{
-}
-
struct vm_struct *alloc_vm_area(size_t size, pte_t **ptes)
{
BUG();
--- a/mm/vmalloc.c~mm-remove-vmalloc_sync_unmappings
+++ a/mm/vmalloc.c
@@ -1350,12 +1350,6 @@ static bool __purge_vmap_area_lazy(unsig
return false;
/*
- * First make sure the mappings are removed from all page-tables
- * before they are freed.
- */
- vmalloc_sync_unmappings();
-
- /*
* TODO: to calculate a flush range without looping.
* The list can be up to lazy_max_pages() elements.
*/
@@ -3085,21 +3079,6 @@ int remap_vmalloc_range(struct vm_area_s
}
EXPORT_SYMBOL(remap_vmalloc_range);
-/*
- * Implement stubs for vmalloc_sync_[un]mappings () if the architecture chose
- * not to have one.
- *
- * The purpose of this function is to make sure the vmalloc area
- * mappings are identical in all page-tables in the system.
- */
-void __weak vmalloc_sync_mappings(void)
-{
-}
-
-void __weak vmalloc_sync_unmappings(void)
-{
-}
-
static int f(pte_t *pte, unsigned long addr, void *data)
{
pte_t ***p = data;
_
Patches currently in -mm which might be from jroedel@xxxxxxx are
mm-add-functions-to-track-page-directory-modifications.patch
mm-vmalloc-track-which-page-table-levels-were-modified.patch
mm-ioremap-track-which-page-table-levels-were-modified.patch
x86-mm-64-implement-arch_sync_kernel_mappings.patch
x86-mm-32-implement-arch_sync_kernel_mappings.patch
mm-remove-vmalloc_sync_unmappings.patch
x86-mm-remove-vmalloc-faulting.patch
