linux/include
Balbir Singh e893bb1bb4 x86, prctl: Hook L1D flushing in via prctl
Use the existing PR_GET/SET_SPECULATION_CTRL API to expose the L1D flush
capability. For L1D flushing PR_SPEC_FORCE_DISABLE and
PR_SPEC_DISABLE_NOEXEC are not supported.

Enabling L1D flush does not check if the task is running on an SMT enabled
core, rather a check is done at runtime (at the time of flush), if the task
runs on a SMT sibling then the task is sent a SIGBUS which is executed
before the task returns to user space or to a guest.

This is better than the other alternatives of:

  a. Ensuring strict affinity of the task (hard to enforce without further
     changes in the scheduler)

  b. Silently skipping flush for tasks that move to SMT enabled cores.

Hook up the core prctl and implement the x86 specific parts which in turn
makes it functional.

Suggested-by: Thomas Gleixner <tglx@linutronix.de>
Signed-off-by: Balbir Singh <sblbir@amazon.com>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Link: https://lore.kernel.org/r/20210108121056.21940-5-sblbir@amazon.com
2021-07-28 11:42:25 +02:00
..
acpi ACPI: fix NULL pointer dereference 2021-07-24 15:25:54 -07:00
asm-generic This pull request contains the following changes for UML: 2021-07-09 10:19:13 -07:00
clocksource clocksource/drivers/timer-ti-dm: Save and restore timer TIOCP_CFG 2021-06-15 14:14:14 +02:00
crypto crypto: scatterwalk - Remove obsolete PageSlab check 2021-06-28 11:28:08 +08:00
drm drm: Return -ENOTTY for non-drm ioctls 2021-07-20 15:57:43 +02:00
dt-bindings dt-bindings: clock: r9a07g044-cpg: Update clock/reset definitions 2021-07-12 10:52:03 +02:00
keys
kunit linux-kselftest-kunit-fixes-5.14-rc1 2021-07-02 12:58:26 -07:00
kvm
linux sched: Add task_work callback for paranoid L1D flush 2021-07-28 11:42:24 +02:00
math-emu math-emu: Fix fall-through warning 2021-07-13 13:57:44 -05:00
media media: Fix Media Controller API config checks 2021-06-24 14:26:00 +02:00
memory
misc
net net/tcp_fastopen: remove obsolete extern 2021-07-20 12:06:33 +02:00
pcmcia
ras
rdma IB/core: Shuffle locks in ib_port_data to save memory 2021-06-21 20:49:32 -03:00
scsi SCSI misc on 20210702 2021-07-02 15:14:36 -07:00
soc Memory controller drivers for v5.14 - Tegra SoC, late fixes 2021-07-16 22:51:01 +02:00
sound ASoC: Fixes for v5.14 2021-07-21 19:48:09 +02:00
target
trace Merge git://git.kernel.org/pub/scm/linux/kernel/git/netdev/net 2021-07-22 10:11:27 -07:00
uapi x86, prctl: Hook L1D flushing in via prctl 2021-07-28 11:42:25 +02:00
vdso
video
xen xen: sync include/xen/interface/io/ring.h with Xen's newest version 2021-07-05 09:49:45 +02:00