5.4-stable patches

added patches:
	mm-hugetlb-allow-for-high-userspace-addresses.patch

diff --git a/queue-5.4/mm-hugetlb-allow-for-high-userspace-addresses.patch b/queue-5.4/mm-hugetlb-allow-for-high-userspace-addresses.patch
new file mode 100644 (file)
index 0000000..591925c
--- /dev/null
+++ b/queue-5.4/mm-hugetlb-allow-for-high-userspace-addresses.patch
@@ -0,0 +1,127 @@
+From 5f24d5a579d1eace79d505b148808a850b417d4c Mon Sep 17 00:00:00 2001
+From: Christophe Leroy <christophe.leroy@csgroup.eu>
+Date: Thu, 21 Apr 2022 16:35:46 -0700
+Subject: mm, hugetlb: allow for "high" userspace addresses
+
+From: Christophe Leroy <christophe.leroy@csgroup.eu>
+
+commit 5f24d5a579d1eace79d505b148808a850b417d4c upstream.
+
+This is a fix for commit f6795053dac8 ("mm: mmap: Allow for "high"
+userspace addresses") for hugetlb.
+
+This patch adds support for "high" userspace addresses that are
+optionally supported on the system and have to be requested via a hint
+mechanism ("high" addr parameter to mmap).
+
+Architectures such as powerpc and x86 achieve this by making changes to
+their architectural versions of hugetlb_get_unmapped_area() function.
+However, arm64 uses the generic version of that function.
+
+So take into account arch_get_mmap_base() and arch_get_mmap_end() in
+hugetlb_get_unmapped_area().  To allow that, move those two macros out
+of mm/mmap.c into include/linux/sched/mm.h
+
+If these macros are not defined in architectural code then they default
+to (TASK_SIZE) and (base) so should not introduce any behavioural
+changes to architectures that do not define them.
+
+For the time being, only ARM64 is affected by this change.
+
+Catalin (ARM64) said
+ "We should have fixed hugetlb_get_unmapped_area() as well when we added
+  support for 52-bit VA. The reason for commit f6795053dac8 was to
+  prevent normal mmap() from returning addresses above 48-bit by default
+  as some user-space had hard assumptions about this.
+
+  It's a slight ABI change if you do this for hugetlb_get_unmapped_area()
+  but I doubt anyone would notice. It's more likely that the current
+  behaviour would cause issues, so I'd rather have them consistent.
+
+  Basically when arm64 gained support for 52-bit addresses we did not
+  want user-space calling mmap() to suddenly get such high addresses,
+  otherwise we could have inadvertently broken some programs (similar
+  behaviour to x86 here). Hence we added commit f6795053dac8. But we
+  missed hugetlbfs which could still get such high mmap() addresses. So
+  in theory that's a potential regression that should have bee addressed
+  at the same time as commit f6795053dac8 (and before arm64 enabled
+  52-bit addresses)"
+
+Link: https://lkml.kernel.org/r/ab847b6edb197bffdfe189e70fb4ac76bfe79e0d.1650033747.git.christophe.leroy@csgroup.eu
+Fixes: f6795053dac8 ("mm: mmap: Allow for "high" userspace addresses")
+Signed-off-by: Christophe Leroy <christophe.leroy@csgroup.eu>
+Reviewed-by: Catalin Marinas <catalin.marinas@arm.com>
+Cc: Steve Capper <steve.capper@arm.com>
+Cc: Will Deacon <will.deacon@arm.com>
+Cc: <stable@vger.kernel.org>   [5.0.x]
+Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
+Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
+Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
+---
+ fs/hugetlbfs/inode.c     |    5 +++--
+ include/linux/sched/mm.h |    8 ++++++++
+ mm/mmap.c                |    8 --------
+ 3 files changed, 11 insertions(+), 10 deletions(-)
+
+--- a/fs/hugetlbfs/inode.c
++++ b/fs/hugetlbfs/inode.c
+@@ -208,6 +208,7 @@ hugetlb_get_unmapped_area(struct file *f
+       struct vm_area_struct *vma;
+       struct hstate *h = hstate_file(file);
+       struct vm_unmapped_area_info info;
++      const unsigned long mmap_end = arch_get_mmap_end(addr);
+ 
+       if (len & ~huge_page_mask(h))
+               return -EINVAL;
+@@ -223,7 +224,7 @@ hugetlb_get_unmapped_area(struct file *f
+       if (addr) {
+               addr = ALIGN(addr, huge_page_size(h));
+               vma = find_vma(mm, addr);
+-              if (TASK_SIZE - len >= addr &&
++              if (mmap_end - len >= addr &&
+                   (!vma || addr + len <= vm_start_gap(vma)))
+                       return addr;
+       }
+@@ -231,7 +232,7 @@ hugetlb_get_unmapped_area(struct file *f
+       info.flags = 0;
+       info.length = len;
+       info.low_limit = TASK_UNMAPPED_BASE;
+-      info.high_limit = TASK_SIZE;
++      info.high_limit = arch_get_mmap_end(addr);
+       info.align_mask = PAGE_MASK & ~huge_page_mask(h);
+       info.align_offset = 0;
+       return vm_unmapped_area(&info);
+--- a/include/linux/sched/mm.h
++++ b/include/linux/sched/mm.h
+@@ -133,6 +133,14 @@ static inline void mm_update_next_owner(
+ #endif /* CONFIG_MEMCG */
+ 
+ #ifdef CONFIG_MMU
++#ifndef arch_get_mmap_end
++#define arch_get_mmap_end(addr)       (TASK_SIZE)
++#endif
++
++#ifndef arch_get_mmap_base
++#define arch_get_mmap_base(addr, base) (base)
++#endif
++
+ extern void arch_pick_mmap_layout(struct mm_struct *mm,
+                                 struct rlimit *rlim_stack);
+ extern unsigned long
+--- a/mm/mmap.c
++++ b/mm/mmap.c
+@@ -2077,14 +2077,6 @@ found_highest:
+ }
+ 
+ 
+-#ifndef arch_get_mmap_end
+-#define arch_get_mmap_end(addr)       (TASK_SIZE)
+-#endif
+-
+-#ifndef arch_get_mmap_base
+-#define arch_get_mmap_base(addr, base) (base)
+-#endif
+-
+ /* Get an address range which is currently unmapped.
+  * For shmat() with addr=0.
+  *

diff --git a/queue-5.4/series b/queue-5.4/series
index fb3ac1327404fbab10aaaee86406d19cf67096e1..9bc614cb3afb1e97bdea8b7e95c046bfaacf9c37 100644 (file)
--- a/queue-5.4/series
+++ b/queue-5.4/series
@@ -80,3 +80,4 @@ tty-n_gsm-fix-missing-explicit-ldisc-flush.patch
 tty-n_gsm-fix-wrong-command-retry-handling.patch
 tty-n_gsm-fix-wrong-command-frame-length-field-encoding.patch
 tty-n_gsm-fix-incorrect-ua-handling.patch
+mm-hugetlb-allow-for-high-userspace-addresses.patch