[rpms/chromium] epel9-next: Support for 64K pages on Linux/AArch64

[rpms/chromium] epel9-next: Support for 64K pages on Linux/AArch64

[Than Ngo]

A new commit has been pushed.

Repo   : rpms/chromium
Branch : epel9-next
Commit : 2a72fc8d8cdfe1d5554eea72b3e30175c16081fd
Author : Than Ngo <than@redhat.com>
Date   : 2024-02-01T17:40:40+01:00
Stats  : +137/-1 in 2 file(s)
URL    : https://src.fedoraproject.org/rpms/chromium/c/2a72fc8d8cdfe1d5554eea72b3e30175c16081fd?branch=epel9-next

Log:
Support for 64K pages on Linux/AArch64

---
diff --git a/chromium-121-el8-support-64kpage.patch b/chromium-121-el8-support-64kpage.patch
new file mode 100644
index 0000000..556fc65
--- /dev/null
+++ b/chromium-121-el8-support-64kpage.patch
@@ -0,0 +1,126 @@
+diff -up chromium-121.0.6167.139/base/allocator/partition_allocator/src/partition_alloc/partition_bucket.h.el8-support-64kpage.patch chromium-121.0.6167.139/base/allocator/partition_allocator/src/partition_alloc/partition_bucket.h
+--- chromium-121.0.6167.139/base/allocator/partition_allocator/src/partition_alloc/partition_bucket.h.el8-support-64kpage.patch	2024-01-30 21:24:10.000000000 +0100
++++ chromium-121.0.6167.139/base/allocator/partition_allocator/src/partition_alloc/partition_bucket.h	2024-02-01 17:20:37.178877448 +0100
+@@ -146,7 +146,13 @@ struct PartitionBucket {
+   // Returns a slot number starting from the beginning of the slot span.
+   PA_ALWAYS_INLINE size_t GetSlotNumber(size_t offset_in_slot_span) const {
+     // See the static assertion for `kReciprocalShift` above.
+-    PA_DCHECK(offset_in_slot_span <= kMaxBucketed);
++    // TODO(casey.smalley@arm.com): triggers on Aarch64/Linux
++    // systems with 64k system pages. Constants need to be
++    // adjusted to prevent different parts of the allocator
++    // from overlapping. For now this will allow 64k pages
++    // to function on Aarch64/Linux systems, albeit not
++    // very efficiently.
++    // PA_DCHECK(offset_in_slot_span <= kMaxBucketed);
+     PA_DCHECK(slot_size <= kMaxBucketed);
+ 
+     const size_t offset_in_slot =
+diff -up chromium-121.0.6167.139/base/allocator/partition_allocator/src/partition_alloc/partition_page_constants.h.el8-support-64kpage.patch chromium-121.0.6167.139/base/allocator/partition_allocator/src/partition_alloc/partition_page_constants.h
+--- chromium-121.0.6167.139/base/allocator/partition_allocator/src/partition_alloc/partition_page_constants.h.el8-support-64kpage.patch	2024-02-01 17:20:37.178877448 +0100
++++ chromium-121.0.6167.139/base/allocator/partition_allocator/src/partition_alloc/partition_page_constants.h	2024-02-01 17:31:08.500268457 +0100
+@@ -17,10 +17,8 @@ namespace partition_alloc::internal {
+ // PartitionPageSize() is 4 times the OS page size.
+ static constexpr size_t kMaxSlotsPerSlotSpan = 4 * (1 << 14) / kSmallestBucket;
+ #elif BUILDFLAG(IS_LINUX) && defined(ARCH_CPU_ARM64)
+-// System page size can be 4, 16, or 64 kiB on Linux on arm64. 64 kiB is
+-// currently (kMaxSlotsPerSlotSpanBits == 13) not supported by the code,
+-// so we use the 16 kiB maximum (64 kiB will crash).
+-static constexpr size_t kMaxSlotsPerSlotSpan = 4 * (1 << 14) / kSmallestBucket;
++// System page size can be 4, 16, or 64 kiB on Linux on AArch64.
++static constexpr size_t kMaxSlotsPerSlotSpan = 4 * (1 << 16) / kSmallestBucket;
+ #else
+ // A slot span can "span" multiple PartitionPages, but then its slot size is
+ // larger, so it doesn't have as many slots.
+diff -up chromium-121.0.6167.139/base/allocator/partition_allocator/src/partition_alloc/partition_page.h.el8-support-64kpage.patch chromium-121.0.6167.139/base/allocator/partition_allocator/src/partition_alloc/partition_page.h
+--- chromium-121.0.6167.139/base/allocator/partition_allocator/src/partition_alloc/partition_page.h.el8-support-64kpage.patch	2024-01-30 21:24:10.000000000 +0100
++++ chromium-121.0.6167.139/base/allocator/partition_allocator/src/partition_alloc/partition_page.h	2024-02-01 17:20:37.178877448 +0100
+@@ -95,26 +95,25 @@ struct SlotSpanMetadata {
+ 
+   // CHECK()ed in AllocNewSlotSpan().
+   // The maximum number of bits needed to cover all currently supported OSes.
+-  static constexpr size_t kMaxSlotsPerSlotSpanBits = 13;
++  static constexpr size_t kMaxSlotsPerSlotSpanBits = 15;
+   static_assert(kMaxSlotsPerSlotSpan < (1 << kMaxSlotsPerSlotSpanBits), "");
+ 
+-  // |marked_full| isn't equivalent to being full. Slot span is marked as full
+-  // iff it isn't on the active slot span list (or any other list).
+-  uint32_t marked_full : 1;
+   // |num_allocated_slots| is 0 for empty or decommitted slot spans, which can
+   // be further differentiated by checking existence of the freelist.
+-  uint32_t num_allocated_slots : kMaxSlotsPerSlotSpanBits;
+-  uint32_t num_unprovisioned_slots : kMaxSlotsPerSlotSpanBits;
++  uint16_t num_allocated_slots : kMaxSlotsPerSlotSpanBits;
++  uint16_t num_unprovisioned_slots : kMaxSlotsPerSlotSpanBits;
++
++  // |marked_full| isn't equivalent to being full. Slot span is marked as full
++  // iff it isn't on the active slot span list (or any other list).
++  bool marked_full : 1;
+ 
+  private:
+-  const uint32_t can_store_raw_size_ : 1;
+-  uint32_t freelist_is_sorted_ : 1;
+-  uint32_t unused1_ : (32 - 1 - 2 * kMaxSlotsPerSlotSpanBits - 1 - 1);
++  const uint8_t can_store_raw_size_ : 1;
++  uint8_t freelist_is_sorted_ : 1;
+   // If |in_empty_cache_|==1, |empty_cache_index| is undefined and mustn't be
+   // used.
+-  uint16_t in_empty_cache_ : 1;
+-  uint16_t empty_cache_index_ : kEmptyCacheIndexBits;  // < kMaxFreeableSpans.
+-  uint16_t unused2_ : (16 - 1 - kEmptyCacheIndexBits);
++  bool in_empty_cache_ : 1;
++  uint8_t empty_cache_index_ : kEmptyCacheIndexBits;  // < kMaxFreeableSpans.
+   // Can use only 48 bits (6B) in this bitfield, as this structure is embedded
+   // in PartitionPage which has 2B worth of fields and must fit in 32B.
+ 
+@@ -279,18 +278,13 @@ static_assert(sizeof(SlotSpanMetadata) <
+               "SlotSpanMetadata must fit into a Page Metadata slot.");
+ 
+ inline constexpr SlotSpanMetadata::SlotSpanMetadata() noexcept
+-    : marked_full(0),
+-      num_allocated_slots(0),
++    : num_allocated_slots(0),
+       num_unprovisioned_slots(0),
++      marked_full(0),
+       can_store_raw_size_(false),
+       freelist_is_sorted_(true),
+-      unused1_(0),
+       in_empty_cache_(0),
+-      empty_cache_index_(0),
+-      unused2_(0) {
+-  (void)unused1_;
+-  (void)unused2_;
+-}
++      empty_cache_index_(0) {}
+ 
+ inline SlotSpanMetadata::SlotSpanMetadata(const SlotSpanMetadata&) = default;
+ 
+@@ -883,7 +877,7 @@ PA_ALWAYS_INLINE void SlotSpanMetadata::
+ 
+   size_t num_slots_per_span = bucket->get_slots_per_span();
+   PA_DCHECK(num_slots_per_span <= kMaxSlotsPerSlotSpan);
+-  num_unprovisioned_slots = static_cast<uint32_t>(num_slots_per_span);
++  num_unprovisioned_slots = static_cast<uint16_t>(num_slots_per_span);
+   PA_DCHECK(num_unprovisioned_slots);
+ 
+   ToSuperPageExtent()->IncrementNumberOfNonemptySlotSpans();
+diff -up chromium-121.0.6167.139/base/allocator/partition_allocator/src/partition_alloc/partition_root.cc.el8-support-64kpage.patch chromium-121.0.6167.139/base/allocator/partition_allocator/src/partition_alloc/partition_root.cc
+--- chromium-121.0.6167.139/base/allocator/partition_allocator/src/partition_alloc/partition_root.cc.el8-support-64kpage.patch	2024-01-30 21:24:10.000000000 +0100
++++ chromium-121.0.6167.139/base/allocator/partition_allocator/src/partition_alloc/partition_root.cc	2024-02-01 17:20:37.178877448 +0100
+@@ -950,12 +950,11 @@ void PartitionRoot::Init(PartitionOption
+              (internal::SystemPageSize() == (size_t{1} << 14)));
+ #elif BUILDFLAG(IS_LINUX) && defined(ARCH_CPU_ARM64)
+     // Check runtime pagesize. Though the code is currently the same, it is
+-    // not merged with the IS_APPLE case above as a 1 << 16 case needs to be
+-    // added here in the future, to allow 64 kiB pagesize. That is only
+-    // supported on Linux on arm64, not on IS_APPLE, but not yet present here
+-    // as the rest of the partition allocator does not currently support it.
++    // not merged with the IS_APPLE case above as a 1 << 16 case is only
++    // supported on Linux on AArch64.
+     PA_CHECK((internal::SystemPageSize() == (size_t{1} << 12)) ||
+-             (internal::SystemPageSize() == (size_t{1} << 14)));
++             (internal::SystemPageSize() == (size_t{1} << 14)) ||
++             (internal::SystemPageSize() == (size_t{1} << 16)));
+ #endif
+ 
+     ::partition_alloc::internal::ScopedGuard guard{lock_};

diff --git a/chromium.spec b/chromium.spec
index 8416e7f..a8c52e3 100644
--- a/chromium.spec
+++ b/chromium.spec
@@ -286,7 +286,7 @@
 
 Name:	chromium%{chromium_channel}
 Version: 121.0.6167.139
-Release: 1%{?dist}
+Release: 2%{?dist}
 Summary: A WebKit (Blink) powered web browser that Google doesn't want you to use
 Url: http://www.chromium.org/Home
 License: BSD-3-Clause AND LGPL-2.1-or-later AND Apache-2.0 AND IJG AND MIT AND GPL-2.0-or-later AND ISC AND OpenSSL AND (MPL-1.1 OR GPL-2.0-only OR LGPL-2.0-only)
@@ -463,6 +463,7 @@ Patch358: chromium-121-rust-clang_lib.patch
 Patch359: chromium-121-python3-invalid-escape-sequence.patch
 
 # upstream patches
+Patch400: chromium-121-el8-support-64kpage.patch
 
 # Use chromium-latest.py to generate clean tarball from released build tarballs, found here:
 # http://build.chromium.org/buildbot/official/
@@ -1082,6 +1083,12 @@ udev.
 %patch -P358 -p1 -b .rust-clang_lib
 %patch -P359 -p1 -b .python3-invalid-escape-sequence
 
+%%ifarch aarch64
+%if 0%{?rhel} == 8
+%patch -P400 -p1 -b .el8-support-64kpage.patch
+%endif
+%endif
+
 # Change shebang in all relevant files in this directory and all subdirectories
 # See `man find` for how the `-exec command {} +` syntax works
 find -type f \( -iname "*.py" \) -exec sed -i '1s=^#! */usr/bin/\(python\|env python\)[23]\?=#!%{__python3}=' {} +
@@ -1796,6 +1803,9 @@ getent group chrome-remote-desktop >/dev/null || groupadd -r chrome-remote-deskt
 %{chromium_path}/chromedriver
 
 %changelog
+* Thu Feb 01 2024 Than Ngo <than@redhat.com> - 121.0.6167.139-2
+- Support for 64K pages on Linux/AArch64
+
 * Wed Jan 31 2024 Than Ngo <than@redhat.com> - 121.0.6167.139-1
 - update to 121.0.6167.139
   * High CVE-2024-1060: Use after free in Canvas