The patch below does not apply to the 6.6-stable tree.
If someone wants it applied there, or to any other stable or longterm
tree, then please email the backport, including the original git commit
id to <stable(a)vger.kernel.org>.
To reproduce the conflict and resubmit, you may use the following commands:
git fetch https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git/ linux-6.6.y
git checkout FETCH_HEAD
git cherry-pick -x 9f98a4f4e7216dbe366010b4cdcab6b220f229c4
# <resolve conflicts, build, test, etc.>
git commit -s
git send-email --to '<stable(a)vger.kernel.org>' --in-reply-to '2025040844-busload-dumpling-45ff@gregkh' --subject-prefix 'PATCH 6.6.y' HEAD^..
Possible dependencies:
thanks,
greg k-h
------------------ original commit in Linus's tree ------------------
From 9f98a4f4e7216dbe366010b4cdcab6b220f229c4 Mon Sep 17 00:00:00 2001
From: Vishal Annapurve <vannapurve(a)google.com>
Date: Fri, 28 Feb 2025 01:44:15 +0000
Subject: [PATCH] x86/tdx: Fix arch_safe_halt() execution for TDX VMs
Direct HLT instruction execution causes #VEs for TDX VMs which is routed
to hypervisor via TDCALL. If HLT is executed in STI-shadow, resulting #VE
handler will enable interrupts before TDCALL is routed to hypervisor
leading to missed wakeup events, as current TDX spec doesn't expose
interruptibility state information to allow #VE handler to selectively
enable interrupts.
Commit bfe6ed0c6727 ("x86/tdx: Add HLT support for TDX guests")
prevented the idle routines from executing HLT instruction in STI-shadow.
But it missed the paravirt routine which can be reached via this path
as an example:
kvm_wait() =>
safe_halt() =>
raw_safe_halt() =>
arch_safe_halt() =>
irq.safe_halt() =>
pv_native_safe_halt()
To reliably handle arch_safe_halt() for TDX VMs, introduce explicit
dependency on CONFIG_PARAVIRT and override paravirt halt()/safe_halt()
routines with TDX-safe versions that execute direct TDCALL and needed
interrupt flag updates. Executing direct TDCALL brings in additional
benefit of avoiding HLT related #VEs altogether.
As tested by Ryan Afranji:
"Tested with the specjbb2015 benchmark. It has heavy lock contention which leads
to many halt calls. TDX VMs suffered a poor score before this patchset.
Verified the major performance improvement with this patchset applied."
Fixes: bfe6ed0c6727 ("x86/tdx: Add HLT support for TDX guests")
Signed-off-by: Vishal Annapurve <vannapurve(a)google.com>
Signed-off-by: Ingo Molnar <mingo(a)kernel.org>
Reviewed-by: Kirill A. Shutemov <kirill.shutemov(a)linux.intel.com>
Tested-by: Ryan Afranji <afranji(a)google.com>
Cc: Andy Lutomirski <luto(a)kernel.org>
Cc: Brian Gerst <brgerst(a)gmail.com>
Cc: Juergen Gross <jgross(a)suse.com>
Cc: H. Peter Anvin <hpa(a)zytor.com>
Cc: Linus Torvalds <torvalds(a)linux-foundation.org>
Cc: Josh Poimboeuf <jpoimboe(a)redhat.com>
Cc: stable(a)vger.kernel.org
Link: https://lore.kernel.org/r/20250228014416.3925664-3-vannapurve@google.com
diff --git a/arch/x86/Kconfig b/arch/x86/Kconfig
index 05b4eca156cf..f614c0522a0b 100644
--- a/arch/x86/Kconfig
+++ b/arch/x86/Kconfig
@@ -878,6 +878,7 @@ config INTEL_TDX_GUEST
depends on X86_64 && CPU_SUP_INTEL
depends on X86_X2APIC
depends on EFI_STUB
+ depends on PARAVIRT
select ARCH_HAS_CC_PLATFORM
select X86_MEM_ENCRYPT
select X86_MCE
diff --git a/arch/x86/coco/tdx/tdx.c b/arch/x86/coco/tdx/tdx.c
index 7772b01ab738..aa0eb4057226 100644
--- a/arch/x86/coco/tdx/tdx.c
+++ b/arch/x86/coco/tdx/tdx.c
@@ -14,6 +14,7 @@
#include <asm/ia32.h>
#include <asm/insn.h>
#include <asm/insn-eval.h>
+#include <asm/paravirt_types.h>
#include <asm/pgtable.h>
#include <asm/set_memory.h>
#include <asm/traps.h>
@@ -398,7 +399,7 @@ static int handle_halt(struct ve_info *ve)
return ve_instr_len(ve);
}
-void __cpuidle tdx_safe_halt(void)
+void __cpuidle tdx_halt(void)
{
const bool irq_disabled = false;
@@ -409,6 +410,16 @@ void __cpuidle tdx_safe_halt(void)
WARN_ONCE(1, "HLT instruction emulation failed\n");
}
+static void __cpuidle tdx_safe_halt(void)
+{
+ tdx_halt();
+ /*
+ * "__cpuidle" section doesn't support instrumentation, so stick
+ * with raw_* variant that avoids tracing hooks.
+ */
+ raw_local_irq_enable();
+}
+
static int read_msr(struct pt_regs *regs, struct ve_info *ve)
{
struct tdx_module_args args = {
@@ -1109,6 +1120,19 @@ void __init tdx_early_init(void)
x86_platform.guest.enc_kexec_begin = tdx_kexec_begin;
x86_platform.guest.enc_kexec_finish = tdx_kexec_finish;
+ /*
+ * Avoid "sti;hlt" execution in TDX guests as HLT induces a #VE that
+ * will enable interrupts before HLT TDCALL invocation if executed
+ * in STI-shadow, possibly resulting in missed wakeup events.
+ *
+ * Modify all possible HLT execution paths to use TDX specific routines
+ * that directly execute TDCALL and toggle the interrupt state as
+ * needed after TDCALL completion. This also reduces HLT related #VEs
+ * in addition to having a reliable halt logic execution.
+ */
+ pv_ops.irq.safe_halt = tdx_safe_halt;
+ pv_ops.irq.halt = tdx_halt;
+
/*
* TDX intercepts the RDMSR to read the X2APIC ID in the parallel
* bringup low level code. That raises #VE which cannot be handled
diff --git a/arch/x86/include/asm/tdx.h b/arch/x86/include/asm/tdx.h
index 65394aa9b49f..4a1922ec80cf 100644
--- a/arch/x86/include/asm/tdx.h
+++ b/arch/x86/include/asm/tdx.h
@@ -58,7 +58,7 @@ void tdx_get_ve_info(struct ve_info *ve);
bool tdx_handle_virt_exception(struct pt_regs *regs, struct ve_info *ve);
-void tdx_safe_halt(void);
+void tdx_halt(void);
bool tdx_early_handle_ve(struct pt_regs *regs);
@@ -72,7 +72,7 @@ void __init tdx_dump_td_ctls(u64 td_ctls);
#else
static inline void tdx_early_init(void) { };
-static inline void tdx_safe_halt(void) { };
+static inline void tdx_halt(void) { };
static inline bool tdx_early_handle_ve(struct pt_regs *regs) { return false; }
diff --git a/arch/x86/kernel/process.c b/arch/x86/kernel/process.c
index 91f6ff618852..962c3ce39323 100644
--- a/arch/x86/kernel/process.c
+++ b/arch/x86/kernel/process.c
@@ -939,7 +939,7 @@ void __init select_idle_routine(void)
static_call_update(x86_idle, mwait_idle);
} else if (cpu_feature_enabled(X86_FEATURE_TDX_GUEST)) {
pr_info("using TDX aware idle routine\n");
- static_call_update(x86_idle, tdx_safe_halt);
+ static_call_update(x86_idle, tdx_halt);
} else {
static_call_update(x86_idle, default_idle);
}
From: Srinivasan Shanmugam <srinivasan.shanmugam(a)amd.com>
commit 15c2990e0f0108b9c3752d7072a97d45d4283aea upstream.
This commit adds null checks for the 'stream' and 'plane' variables in
the dcn30_apply_idle_power_optimizations function. These variables were
previously assumed to be null at line 922, but they were used later in
the code without checking if they were null. This could potentially lead
to a null pointer dereference, which would cause a crash.
The null checks ensure that 'stream' and 'plane' are not null before
they are used, preventing potential crashes.
Fixes the below static smatch checker:
drivers/gpu/drm/amd/amdgpu/../display/dc/hwss/dcn30/dcn30_hwseq.c:938 dcn30_apply_idle_power_optimizations() error: we previously assumed 'stream' could be null (see line 922)
drivers/gpu/drm/amd/amdgpu/../display/dc/hwss/dcn30/dcn30_hwseq.c:940 dcn30_apply_idle_power_optimizations() error: we previously assumed 'plane' could be null (see line 922)
Cc: Tom Chung <chiahsuan.chung(a)amd.com>
Cc: Nicholas Kazlauskas <nicholas.kazlauskas(a)amd.com>
Cc: Bhawanpreet Lakha <Bhawanpreet.Lakha(a)amd.com>
Cc: Rodrigo Siqueira <Rodrigo.Siqueira(a)amd.com>
Cc: Roman Li <roman.li(a)amd.com>
Cc: Hersen Wu <hersenxs.wu(a)amd.com>
Cc: Alex Hung <alex.hung(a)amd.com>
Cc: Aurabindo Pillai <aurabindo.pillai(a)amd.com>
Cc: Harry Wentland <harry.wentland(a)amd.com>
Signed-off-by: Srinivasan Shanmugam <srinivasan.shanmugam(a)amd.com>
Reviewed-by: Aurabindo Pillai <aurabindo.pillai(a)amd.com>
Signed-off-by: Alex Deucher <alexander.deucher(a)amd.com>
Signed-off-by: Zhi Yang <Zhi.Yang(a)windriver.com>
Signed-off-by: He Zhe <zhe.he(a)windriver.com>
---
Build test passed.
---
drivers/gpu/drm/amd/display/dc/dcn30/dcn30_hwseq.c | 3 +++
1 file changed, 3 insertions(+)
diff --git a/drivers/gpu/drm/amd/display/dc/dcn30/dcn30_hwseq.c b/drivers/gpu/drm/amd/display/dc/dcn30/dcn30_hwseq.c
index 81547178a934..30716b88136c 100644
--- a/drivers/gpu/drm/amd/display/dc/dcn30/dcn30_hwseq.c
+++ b/drivers/gpu/drm/amd/display/dc/dcn30/dcn30_hwseq.c
@@ -784,6 +784,9 @@ bool dcn30_apply_idle_power_optimizations(struct dc *dc, bool enable)
stream = dc->current_state->streams[0];
plane = (stream ? dc->current_state->stream_status[0].plane_states[0] : NULL);
+ if (!stream || !plane)
+ return false;
+
if (stream && plane) {
cursor_cache_enable = stream->cursor_position.enable &&
plane->address.grph.cursor_cache_addr.quad_part;
--
2.34.1
The patch below does not apply to the 6.13-stable tree.
If someone wants it applied there, or to any other stable or longterm
tree, then please email the backport, including the original git commit
id to <stable(a)vger.kernel.org>.
To reproduce the conflict and resubmit, you may use the following commands:
git fetch https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git/ linux-6.13.y
git checkout FETCH_HEAD
git cherry-pick -x dd4f730b557ce701a2cd4f604bf1e57667bd8b6e
# <resolve conflicts, build, test, etc.>
git commit -s
git send-email --to '<stable(a)vger.kernel.org>' --in-reply-to '2025040803-womb-decorated-10be@gregkh' --subject-prefix 'PATCH 6.13.y' HEAD^..
Possible dependencies:
thanks,
greg k-h
------------------ original commit in Linus's tree ------------------
From dd4f730b557ce701a2cd4f604bf1e57667bd8b6e Mon Sep 17 00:00:00 2001
From: Nathan Chancellor <nathan(a)kernel.org>
Date: Mon, 10 Feb 2025 21:28:25 -0500
Subject: [PATCH] ACPI: platform-profile: Fix CFI violation when accessing
sysfs files
When an attribute group is created with sysfs_create_group(), the
->sysfs_ops() callback is set to kobj_sysfs_ops, which sets the ->show()
and ->store() callbacks to kobj_attr_show() and kobj_attr_store()
respectively. These functions use container_of() to get the respective
callback from the passed attribute, meaning that these callbacks need to
be of the same type as the callbacks in 'struct kobj_attribute'.
However, ->show() and ->store() in the platform_profile driver are
defined for struct device_attribute with the help of DEVICE_ATTR_RO()
and DEVICE_ATTR_RW(), which results in a CFI violation when accessing
platform_profile or platform_profile_choices under /sys/firmware/acpi
because the types do not match:
CFI failure at kobj_attr_show+0x19/0x30 (target: platform_profile_choices_show+0x0/0x140; expected type: 0x7a69590c)
There is no functional issue from the type mismatch because the layout
of 'struct kobj_attribute' and 'struct device_attribute' are the same,
so the container_of() cast does not break anything aside from CFI.
Change the type of platform_profile_choices_show() and
platform_profile_{show,store}() to match the callbacks in
'struct kobj_attribute' and update the attribute variables to
match, which resolves the CFI violation.
Cc: All applicable <stable(a)vger.kernel.org>
Fixes: a2ff95e018f1 ("ACPI: platform: Add platform profile support")
Reported-by: John Rowley <lkml(a)johnrowley.me>
Closes: https://github.com/ClangBuiltLinux/linux/issues/2047
Tested-by: John Rowley <lkml(a)johnrowley.me>
Reviewed-by: Sami Tolvanen <samitolvanen(a)google.com>
Signed-off-by: Nathan Chancellor <nathan(a)kernel.org>
Acked-by: Greg Kroah-Hartman <gregkh(a)linuxfoundation.org>
Reviewed-by: Mark Pearson <mpearson-lenovo(a)squebb.ca>
Tested-by: Mark Pearson <mpearson-lenovo(a)squebb.ca>
Link: https://patch.msgid.link/20250210-acpi-platform_profile-fix-cfi-violation-v…
[ rjw: Changelog edits ]
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki(a)intel.com>
diff --git a/drivers/acpi/platform_profile.c b/drivers/acpi/platform_profile.c
index fc92e43d0fe9..1b6317f759f9 100644
--- a/drivers/acpi/platform_profile.c
+++ b/drivers/acpi/platform_profile.c
@@ -260,14 +260,14 @@ static int _aggregate_choices(struct device *dev, void *data)
/**
* platform_profile_choices_show - Show the available profile choices for legacy sysfs interface
- * @dev: The device
+ * @kobj: The kobject
* @attr: The attribute
* @buf: The buffer to write to
*
* Return: The number of bytes written
*/
-static ssize_t platform_profile_choices_show(struct device *dev,
- struct device_attribute *attr,
+static ssize_t platform_profile_choices_show(struct kobject *kobj,
+ struct kobj_attribute *attr,
char *buf)
{
unsigned long aggregate[BITS_TO_LONGS(PLATFORM_PROFILE_LAST)];
@@ -333,14 +333,14 @@ static int _store_and_notify(struct device *dev, void *data)
/**
* platform_profile_show - Show the current profile for legacy sysfs interface
- * @dev: The device
+ * @kobj: The kobject
* @attr: The attribute
* @buf: The buffer to write to
*
* Return: The number of bytes written
*/
-static ssize_t platform_profile_show(struct device *dev,
- struct device_attribute *attr,
+static ssize_t platform_profile_show(struct kobject *kobj,
+ struct kobj_attribute *attr,
char *buf)
{
enum platform_profile_option profile = PLATFORM_PROFILE_LAST;
@@ -362,15 +362,15 @@ static ssize_t platform_profile_show(struct device *dev,
/**
* platform_profile_store - Set the profile for legacy sysfs interface
- * @dev: The device
+ * @kobj: The kobject
* @attr: The attribute
* @buf: The buffer to read from
* @count: The number of bytes to read
*
* Return: The number of bytes read
*/
-static ssize_t platform_profile_store(struct device *dev,
- struct device_attribute *attr,
+static ssize_t platform_profile_store(struct kobject *kobj,
+ struct kobj_attribute *attr,
const char *buf, size_t count)
{
unsigned long choices[BITS_TO_LONGS(PLATFORM_PROFILE_LAST)];
@@ -401,12 +401,12 @@ static ssize_t platform_profile_store(struct device *dev,
return count;
}
-static DEVICE_ATTR_RO(platform_profile_choices);
-static DEVICE_ATTR_RW(platform_profile);
+static struct kobj_attribute attr_platform_profile_choices = __ATTR_RO(platform_profile_choices);
+static struct kobj_attribute attr_platform_profile = __ATTR_RW(platform_profile);
static struct attribute *platform_profile_attrs[] = {
- &dev_attr_platform_profile_choices.attr,
- &dev_attr_platform_profile.attr,
+ &attr_platform_profile_choices.attr,
+ &attr_platform_profile.attr,
NULL
};