commit 6f946aad974af89c2c58e0648ed328a49842bf59
author Jeffrey Gour <jegour@microsoft.com> Thu Jul 11 16:07:54 2024
committer Chromium LUCI CQ <chromium-scoped@luci-project-accounts.iam.gserviceaccount.com> Thu Jul 11 16:07:54 2024
tree 262618666f919b224545c2a6c47725547d1e6d64
parent a7e3fb084cfb7b7ab0bdc235e9efe6f2854c9989

Reland "Make static initialization of base::ProtectedMemory objects required"

This is a reland of commit 7f04022ea0ca8cd4f2195f0bcbeca4ba7f8fb2f6.
The original commit was reverted due to test failures in component
builds. These failures came in two flavors and this reland contains
fixes for both. They are:

1. Failures caused by the ProtectedMemory variable being initialized
not being in the proper memory address range. This is caused by the
memory segment code being defined in the .h file which means that
different DSOs can define different sections, and cross DSO calls
will show the memory in the wrong section. The fix is simply to
disable ProtectedMemory for component builds. Component builds are
never shipped so there is no value in supporting it for them.
2. The new get_{{feature.data_member_name}}() method added for
ProtectedMemory RuntimeEnabledFeatures, which is the method where the
static initializer was added, was defined in the include file instead
of the cc file. Thus the static initializer could be rerun in different DSOs. This resulted in the MojoJS runtime enabled feature
not necessarily getting the right value, causing tests that needed it
to be true to fail with MojoInterfaceInterceptor (because MojoJS
bindings weren't enabled). By moving the definition to the CC file,
this problem went away.

Original change's description:
> Make static initialization of base::ProtectedMemory objects required
>
> This change makes it so that static initialization of
> base::ProtectedMemory instances is always required, even if the type
> provides constant initialization. This achieved by removing the bool
> ConstructLazily template parameter from ProtectedMemory and related
> classes, and making the case where it's "true" the only case. Thus the
> lazy construction through base::ProtectedMemoryInitializer is required.
>
> This change is made in preparation of adding support for ProtectedMemory
> to non-windows platforms. On some platforms there is an issue with
> initializing the protected memory section to readonly at build/link
> time. To combat this, the required initialization of ProtectedMemory
> instances will be used to initialize the protected section to readonly
> at runtime.
>
> This change also updates previously added use cases of ProtectedMemory
> to add the now required initialization.
>
> Bug: 41495919
> Change-Id: Ice3d39caee28a3fc956d4d9ebca8c6f51d03ce1c
> Reviewed-on: https://chromium-review.googlesource.com/c/chromium/src/+/5668250
> Commit-Queue: Jeffrey Gour <jegour@microsoft.com>
> Reviewed-by: Daniel Cheng <dcheng@chromium.org>
> Reviewed-by: Dave Tapuska <dtapuska@chromium.org>
> Cr-Commit-Position: refs/heads/main@{#1324440}

Bug: 41495919
Change-Id: Ic8d416e4278d1bddf892e0ba967999b3ba4e8f1b
Reviewed-on: https://chromium-review.googlesource.com/c/chromium/src/+/5689823
Reviewed-by: Daniel Cheng <dcheng@chromium.org>
Reviewed-by: Dave Tapuska <dtapuska@chromium.org>
Commit-Queue: Jeffrey Gour <jegour@microsoft.com>
Cr-Commit-Position: refs/heads/main@{#1326184}