6.8-stable patches

added patches:
	irqflags-explicitly-ignore-lockdep_hrtimer_exit-argument.patch
	kernfs-annotate-different-lockdep-class-for-of-mutex-of-writable-files.patch
	selftests-kselftest-fix-build-failure-with-nolibc.patch
	x86-bugs-cache-the-value-of-msr_ia32_arch_capabilities.patch
	x86-bugs-fix-bhi-documentation.patch

6 files changed, 359 insertions, 1 deletions

diff --git a/queue-6.8/irqflags-explicitly-ignore-lockdep_hrtimer_exit-argument.patch b/queue-6.8/irqflags-explicitly-ignore-lockdep_hrtimer_exit-argument.patch
new file mode 100644
index 0000000000..2c1cd648fc
--- /dev/null
+++ b/queue-6.8/irqflags-explicitly-ignore-lockdep_hrtimer_exit-argument.patch
@@ -0,0 +1,40 @@
+From c1d11fc2c8320871b40730991071dd0a0b405bc8 Mon Sep 17 00:00:00 2001
+From: Arnd Bergmann <arnd@arndb.de>
+Date: Mon, 8 Apr 2024 09:46:01 +0200
+Subject: irqflags: Explicitly ignore lockdep_hrtimer_exit() argument
+
+From: Arnd Bergmann <arnd@arndb.de>
+
+commit c1d11fc2c8320871b40730991071dd0a0b405bc8 upstream.
+
+When building with 'make W=1' but CONFIG_TRACE_IRQFLAGS=n, the
+unused argument to lockdep_hrtimer_exit() causes a warning:
+
+kernel/time/hrtimer.c:1655:14: error: variable 'expires_in_hardirq' set but not used [-Werror=unused-but-set-variable]
+
+This is intentional behavior, so add a cast to void to shut up the warning.
+
+Fixes: 73d20564e0dc ("hrtimer: Don't dereference the hrtimer pointer after the callback")
+Reported-by: kernel test robot <lkp@intel.com>
+Signed-off-by: Arnd Bergmann <arnd@arndb.de>
+Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
+Reviewed-by: Sebastian Andrzej Siewior <bigeasy@linutronix.de>
+Cc: stable@vger.kernel.org
+Link: https://lore.kernel.org/r/20240408074609.3170807-1-arnd@kernel.org
+Closes: https://lore.kernel.org/oe-kbuild-all/202311191229.55QXHVc6-lkp@intel.com/
+Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
+---
+ include/linux/irqflags.h |    2 +-
+ 1 file changed, 1 insertion(+), 1 deletion(-)
+
+--- a/include/linux/irqflags.h
++++ b/include/linux/irqflags.h
+@@ -114,7 +114,7 @@ do {						\
+ # define lockdep_softirq_enter()		do { } while (0)
+ # define lockdep_softirq_exit()			do { } while (0)
+ # define lockdep_hrtimer_enter(__hrtimer)	false
+-# define lockdep_hrtimer_exit(__context)	do { } while (0)
++# define lockdep_hrtimer_exit(__context)	do { (void)(__context); } while (0)
+ # define lockdep_posixtimer_enter()		do { } while (0)
+ # define lockdep_posixtimer_exit()		do { } while (0)
+ # define lockdep_irq_work_enter(__work)		do { } while (0)
diff --git a/queue-6.8/kernfs-annotate-different-lockdep-class-for-of-mutex-of-writable-files.patch b/queue-6.8/kernfs-annotate-different-lockdep-class-for-of-mutex-of-writable-files.patch
new file mode 100644
index 0000000000..c1b25aad23
--- /dev/null
+++ b/queue-6.8/kernfs-annotate-different-lockdep-class-for-of-mutex-of-writable-files.patch
@@ -0,0 +1,49 @@
+From 16b52bbee4823b01ab7fe3919373c981a38f3797 Mon Sep 17 00:00:00 2001
+From: Amir Goldstein <amir73il@gmail.com>
+Date: Fri, 5 Apr 2024 17:56:35 +0300
+Subject: kernfs: annotate different lockdep class for of->mutex of writable files
+
+From: Amir Goldstein <amir73il@gmail.com>
+
+commit 16b52bbee4823b01ab7fe3919373c981a38f3797 upstream.
+
+The writable file /sys/power/resume may call vfs lookup helpers for
+arbitrary paths and readonly files can be read by overlayfs from vfs
+helpers when sysfs is a lower layer of overalyfs.
+
+To avoid a lockdep warning of circular dependency between overlayfs
+inode lock and kernfs of->mutex, use a different lockdep class for
+writable and readonly kernfs files.
+
+Reported-by: syzbot+9a5b0ced8b1bfb238b56@syzkaller.appspotmail.com
+Fixes: 0fedefd4c4e3 ("kernfs: sysfs: support custom llseek method for sysfs entries")
+Suggested-by: Al Viro <viro@zeniv.linux.org.uk>
+Signed-off-by: Amir Goldstein <amir73il@gmail.com>
+Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
+Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
+---
+ fs/kernfs/file.c |    9 ++++++++-
+ 1 file changed, 8 insertions(+), 1 deletion(-)
+
+--- a/fs/kernfs/file.c
++++ b/fs/kernfs/file.c
+@@ -634,11 +634,18 @@ static int kernfs_fop_open(struct inode
+ 	 * each file a separate locking class.  Let's differentiate on
+ 	 * whether the file has mmap or not for now.
+ 	 *
+-	 * Both paths of the branch look the same.  They're supposed to
++	 * For similar reasons, writable and readonly files are given different
++	 * lockdep key, because the writable file /sys/power/resume may call vfs
++	 * lookup helpers for arbitrary paths and readonly files can be read by
++	 * overlayfs from vfs helpers when sysfs is a lower layer of overalyfs.
++	 *
++	 * All three cases look the same.  They're supposed to
+ 	 * look that way and give @of->mutex different static lockdep keys.
+ 	 */
+ 	if (has_mmap)
+ 		mutex_init(&of->mutex);
++	else if (file->f_mode & FMODE_WRITE)
++		mutex_init(&of->mutex);
+ 	else
+ 		mutex_init(&of->mutex);
+ 
diff --git a/queue-6.8/selftests-kselftest-fix-build-failure-with-nolibc.patch b/queue-6.8/selftests-kselftest-fix-build-failure-with-nolibc.patch
new file mode 100644
index 0000000000..c6a10374ab
--- /dev/null
+++ b/queue-6.8/selftests-kselftest-fix-build-failure-with-nolibc.patch
@@ -0,0 +1,44 @@
+From 16767502aa990cca2cb7d1372b31d328c4c85b40 Mon Sep 17 00:00:00 2001
+From: Oleg Nesterov <oleg@redhat.com>
+Date: Fri, 12 Apr 2024 14:35:36 +0200
+Subject: selftests: kselftest: Fix build failure with NOLIBC
+
+From: Oleg Nesterov <oleg@redhat.com>
+
+commit 16767502aa990cca2cb7d1372b31d328c4c85b40 upstream.
+
+As Mark explains ksft_min_kernel_version() can't be compiled with nolibc,
+it doesn't implement uname().
+
+Fixes: 6d029c25b71f ("selftests/timers/posix_timers: Reimplement check_timer_distribution()")
+Reported-by: Mark Brown <broonie@kernel.org>
+Signed-off-by: Oleg Nesterov <oleg@redhat.com>
+Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
+Link: https://lore.kernel.org/r/20240412123536.GA32444@redhat.com
+Closes: https://lore.kernel.org/all/f0523b3a-ea08-4615-b0fb-5b504a2d39df@sirena.org.uk/
+Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
+---
+ tools/testing/selftests/kselftest.h |    5 +++++
+ 1 file changed, 5 insertions(+)
+
+--- a/tools/testing/selftests/kselftest.h
++++ b/tools/testing/selftests/kselftest.h
+@@ -350,6 +350,10 @@ static inline __noreturn __printf(1, 2)
+ static inline int ksft_min_kernel_version(unsigned int min_major,
+ 					  unsigned int min_minor)
+ {
++#ifdef NOLIBC
++	ksft_print_msg("NOLIBC: Can't check kernel version: Function not implemented\n");
++	return 0;
++#else
+ 	unsigned int major, minor;
+ 	struct utsname info;
+ 
+@@ -357,6 +361,7 @@ static inline int ksft_min_kernel_versio
+ 		ksft_exit_fail_msg("Can't parse kernel version\n");
+ 
+ 	return major > min_major || (major == min_major && minor >= min_minor);
++#endif
+ }
+ 
+ #endif /* __KSELFTEST_H */
diff --git a/queue-6.8/series b/queue-6.8/series
index f866ecb127..740eb0ef33 100644
--- a/queue-6.8/series
+++ b/queue-6.8/series
@@ -99,7 +99,6 @@ net-ena-fix-incorrect-descriptor-free-behavior.patch
 net-ena-set-tx_info-xdpf-value-to-null.patch
 drm-xe-display-fix-double-mutex-initialization.patch
 drm-xe-hwmon-cast-result-to-output-precision-on-left.patch
-tracing-fix-ftrace_record_recursion_size-kconfig-ent.patch
 tracing-hide-unused-ftrace_event_id_fops.patch
 iommu-vt-d-fix-wrong-use-of-pasid-config.patch
 iommu-vt-d-allocate-local-memory-for-page-request-qu.patch
@@ -146,3 +145,8 @@ selftests-timers-fix-posix_timers-ksft_print_msg-warning.patch
 selftests-timers-fix-abs-warning-in-posix_timers-test.patch
 selftests-kselftest-mark-functions-that-unconditionally-call-exit-as-__noreturn.patch
 x86-apic-force-native_apic_mem_read-to-use-the-mov-instruction.patch
+irqflags-explicitly-ignore-lockdep_hrtimer_exit-argument.patch
+selftests-kselftest-fix-build-failure-with-nolibc.patch
+kernfs-annotate-different-lockdep-class-for-of-mutex-of-writable-files.patch
+x86-bugs-fix-bhi-documentation.patch
+x86-bugs-cache-the-value-of-msr_ia32_arch_capabilities.patch
diff --git a/queue-6.8/x86-bugs-cache-the-value-of-msr_ia32_arch_capabilities.patch b/queue-6.8/x86-bugs-cache-the-value-of-msr_ia32_arch_capabilities.patch
new file mode 100644
index 0000000000..8c48f5d6fa
--- /dev/null
+++ b/queue-6.8/x86-bugs-cache-the-value-of-msr_ia32_arch_capabilities.patch
@@ -0,0 +1,133 @@
+From cb2db5bb04d7f778fbc1a1ea2507aab436f1bff3 Mon Sep 17 00:00:00 2001
+From: Josh Poimboeuf <jpoimboe@kernel.org>
+Date: Wed, 10 Apr 2024 22:40:46 -0700
+Subject: x86/bugs: Cache the value of MSR_IA32_ARCH_CAPABILITIES
+
+From: Josh Poimboeuf <jpoimboe@kernel.org>
+
+commit cb2db5bb04d7f778fbc1a1ea2507aab436f1bff3 upstream.
+
+There's no need to keep reading MSR_IA32_ARCH_CAPABILITIES over and
+over.  It's even read in the BHI sysfs function which is a big no-no.
+Just read it once and cache it.
+
+Fixes: ec9404e40e8f ("x86/bhi: Add BHI mitigation knob")
+Signed-off-by: Josh Poimboeuf <jpoimboe@kernel.org>
+Signed-off-by: Ingo Molnar <mingo@kernel.org>
+Reviewed-by: Nikolay Borisov <nik.borisov@suse.com>
+Cc: Linus Torvalds <torvalds@linux-foundation.org>
+Cc: Sean Christopherson <seanjc@google.com>
+Link: https://lore.kernel.org/r/9592a18a814368e75f8f4b9d74d3883aa4fd1eaf.1712813475.git.jpoimboe@kernel.org
+Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
+---
+ arch/x86/kernel/cpu/bugs.c |   22 +++++++---------------
+ 1 file changed, 7 insertions(+), 15 deletions(-)
+
+--- a/arch/x86/kernel/cpu/bugs.c
++++ b/arch/x86/kernel/cpu/bugs.c
+@@ -61,6 +61,8 @@ EXPORT_SYMBOL_GPL(x86_spec_ctrl_current)
+ u64 x86_pred_cmd __ro_after_init = PRED_CMD_IBPB;
+ EXPORT_SYMBOL_GPL(x86_pred_cmd);
+ 
++static u64 __ro_after_init ia32_cap;
++
+ static DEFINE_MUTEX(spec_ctrl_mutex);
+ 
+ void (*x86_return_thunk)(void) __ro_after_init = __x86_return_thunk;
+@@ -144,6 +146,8 @@ void __init cpu_select_mitigations(void)
+ 		x86_spec_ctrl_base &= ~SPEC_CTRL_MITIGATIONS_MASK;
+ 	}
+ 
++	ia32_cap = x86_read_arch_cap_msr();
++
+ 	/* Select the proper CPU mitigations before patching alternatives: */
+ 	spectre_v1_select_mitigation();
+ 	spectre_v2_select_mitigation();
+@@ -301,8 +305,6 @@ static const char * const taa_strings[]
+ 
+ static void __init taa_select_mitigation(void)
+ {
+-	u64 ia32_cap;
+-
+ 	if (!boot_cpu_has_bug(X86_BUG_TAA)) {
+ 		taa_mitigation = TAA_MITIGATION_OFF;
+ 		return;
+@@ -341,7 +343,6 @@ static void __init taa_select_mitigation
+ 	 * On MDS_NO=1 CPUs if ARCH_CAP_TSX_CTRL_MSR is not set, microcode
+ 	 * update is required.
+ 	 */
+-	ia32_cap = x86_read_arch_cap_msr();
+ 	if ( (ia32_cap & ARCH_CAP_MDS_NO) &&
+ 	    !(ia32_cap & ARCH_CAP_TSX_CTRL_MSR))
+ 		taa_mitigation = TAA_MITIGATION_UCODE_NEEDED;
+@@ -401,8 +402,6 @@ static const char * const mmio_strings[]
+ 
+ static void __init mmio_select_mitigation(void)
+ {
+-	u64 ia32_cap;
+-
+ 	if (!boot_cpu_has_bug(X86_BUG_MMIO_STALE_DATA) ||
+ 	     boot_cpu_has_bug(X86_BUG_MMIO_UNKNOWN) ||
+ 	     cpu_mitigations_off()) {
+@@ -413,8 +412,6 @@ static void __init mmio_select_mitigatio
+ 	if (mmio_mitigation == MMIO_MITIGATION_OFF)
+ 		return;
+ 
+-	ia32_cap = x86_read_arch_cap_msr();
+-
+ 	/*
+ 	 * Enable CPU buffer clear mitigation for host and VMM, if also affected
+ 	 * by MDS or TAA. Otherwise, enable mitigation for VMM only.
+@@ -508,7 +505,7 @@ static void __init rfds_select_mitigatio
+ 	if (rfds_mitigation == RFDS_MITIGATION_OFF)
+ 		return;
+ 
+-	if (x86_read_arch_cap_msr() & ARCH_CAP_RFDS_CLEAR)
++	if (ia32_cap & ARCH_CAP_RFDS_CLEAR)
+ 		setup_force_cpu_cap(X86_FEATURE_CLEAR_CPU_BUF);
+ 	else
+ 		rfds_mitigation = RFDS_MITIGATION_UCODE_NEEDED;
+@@ -659,8 +656,6 @@ void update_srbds_msr(void)
+ 
+ static void __init srbds_select_mitigation(void)
+ {
+-	u64 ia32_cap;
+-
+ 	if (!boot_cpu_has_bug(X86_BUG_SRBDS))
+ 		return;
+ 
+@@ -669,7 +664,6 @@ static void __init srbds_select_mitigati
+ 	 * are only exposed to SRBDS when TSX is enabled or when CPU is affected
+ 	 * by Processor MMIO Stale Data vulnerability.
+ 	 */
+-	ia32_cap = x86_read_arch_cap_msr();
+ 	if ((ia32_cap & ARCH_CAP_MDS_NO) && !boot_cpu_has(X86_FEATURE_RTM) &&
+ 	    !boot_cpu_has_bug(X86_BUG_MMIO_STALE_DATA))
+ 		srbds_mitigation = SRBDS_MITIGATION_TSX_OFF;
+@@ -813,7 +807,7 @@ static void __init gds_select_mitigation
+ 	/* Will verify below that mitigation _can_ be disabled */
+ 
+ 	/* No microcode */
+-	if (!(x86_read_arch_cap_msr() & ARCH_CAP_GDS_CTRL)) {
++	if (!(ia32_cap & ARCH_CAP_GDS_CTRL)) {
+ 		if (gds_mitigation == GDS_MITIGATION_FORCE) {
+ 			/*
+ 			 * This only needs to be done on the boot CPU so do it
+@@ -1907,8 +1901,6 @@ static void update_indir_branch_cond(voi
+ /* Update the static key controlling the MDS CPU buffer clear in idle */
+ static void update_mds_branch_idle(void)
+ {
+-	u64 ia32_cap = x86_read_arch_cap_msr();
+-
+ 	/*
+ 	 * Enable the idle clearing if SMT is active on CPUs which are
+ 	 * affected only by MSBDS and not any other MDS variant.
+@@ -2817,7 +2809,7 @@ static const char * const spectre_bhi_st
+ 	else if  (boot_cpu_has(X86_FEATURE_CLEAR_BHB_LOOP))
+ 		return "; BHI: SW loop, KVM: SW loop";
+ 	else if (boot_cpu_has(X86_FEATURE_RETPOLINE) &&
+-		 !(x86_read_arch_cap_msr() & ARCH_CAP_RRSBA))
++		 !(ia32_cap & ARCH_CAP_RRSBA))
+ 		return "; BHI: Retpoline";
+ 	else if  (boot_cpu_has(X86_FEATURE_CLEAR_BHB_LOOP_ON_VMEXIT))
+ 		return "; BHI: Syscall hardening, KVM: SW loop";
diff --git a/queue-6.8/x86-bugs-fix-bhi-documentation.patch b/queue-6.8/x86-bugs-fix-bhi-documentation.patch
new file mode 100644
index 0000000000..6045db3326
--- /dev/null
+++ b/queue-6.8/x86-bugs-fix-bhi-documentation.patch
@@ -0,0 +1,88 @@
+From dfe648903f42296866d79f10d03f8c85c9dfba30 Mon Sep 17 00:00:00 2001
+From: Josh Poimboeuf <jpoimboe@kernel.org>
+Date: Wed, 10 Apr 2024 22:40:45 -0700
+Subject: x86/bugs: Fix BHI documentation
+
+From: Josh Poimboeuf <jpoimboe@kernel.org>
+
+commit dfe648903f42296866d79f10d03f8c85c9dfba30 upstream.
+
+Fix up some inaccuracies in the BHI documentation.
+
+Fixes: ec9404e40e8f ("x86/bhi: Add BHI mitigation knob")
+Signed-off-by: Josh Poimboeuf <jpoimboe@kernel.org>
+Signed-off-by: Ingo Molnar <mingo@kernel.org>
+Reviewed-by: Nikolay Borisov <nik.borisov@suse.com>
+Cc: Linus Torvalds <torvalds@linux-foundation.org>
+Cc: Sean Christopherson <seanjc@google.com>
+Link: https://lore.kernel.org/r/8c84f7451bfe0dd08543c6082a383f390d4aa7e2.1712813475.git.jpoimboe@kernel.org
+Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
+---
+ Documentation/admin-guide/hw-vuln/spectre.rst   |   15 ++++++++-------
+ Documentation/admin-guide/kernel-parameters.txt |   12 +++++++-----
+ 2 files changed, 15 insertions(+), 12 deletions(-)
+
+--- a/Documentation/admin-guide/hw-vuln/spectre.rst
++++ b/Documentation/admin-guide/hw-vuln/spectre.rst
+@@ -439,11 +439,11 @@ The possible values in this file are:
+    - System is protected by retpoline
+  * - BHI: BHI_DIS_S
+    - System is protected by BHI_DIS_S
+- * - BHI: SW loop; KVM SW loop
++ * - BHI: SW loop, KVM SW loop
+    - System is protected by software clearing sequence
+  * - BHI: Syscall hardening
+    - Syscalls are hardened against BHI
+- * - BHI: Syscall hardening; KVM: SW loop
++ * - BHI: Syscall hardening, KVM: SW loop
+    - System is protected from userspace attacks by syscall hardening; KVM is protected by software clearing sequence
+ 
+ Full mitigation might require a microcode update from the CPU
+@@ -666,13 +666,14 @@ kernel command line.
+ 		of the HW BHI control and the SW BHB clearing sequence.
+ 
+ 		on
+-			unconditionally enable.
++			(default) Enable the HW or SW mitigation as
++			needed.
+ 		off
+-			unconditionally disable.
++			Disable the mitigation.
+ 		auto
+-			enable if hardware mitigation
+-			control(BHI_DIS_S) is available, otherwise
+-			enable alternate mitigation in KVM.
++			Enable the HW mitigation if needed, but
++			*don't* enable the SW mitigation except for KVM.
++			The system may be vulnerable.
+ 
+ For spectre_v2_user see Documentation/admin-guide/kernel-parameters.txt
+ 
+--- a/Documentation/admin-guide/kernel-parameters.txt
++++ b/Documentation/admin-guide/kernel-parameters.txt
+@@ -3419,6 +3419,7 @@
+ 					       reg_file_data_sampling=off [X86]
+ 					       retbleed=off [X86]
+ 					       spec_store_bypass_disable=off [X86,PPC]
++					       spectre_bhi=off [X86]
+ 					       spectre_v2_user=off [X86]
+ 					       srbds=off [X86,INTEL]
+ 					       ssbd=force-off [ARM64]
+@@ -6037,11 +6038,12 @@
+ 			deployment of the HW BHI control and the SW BHB
+ 			clearing sequence.
+ 
+-			on   - unconditionally enable.
+-			off  - unconditionally disable.
+-			auto - (default) enable hardware mitigation
+-			       (BHI_DIS_S) if available, otherwise enable
+-			       alternate mitigation in KVM.
++			on   - (default) Enable the HW or SW mitigation
++			       as needed.
++			off  - Disable the mitigation.
++			auto - Enable the HW mitigation if needed, but
++			       *don't* enable the SW mitigation except
++			       for KVM.  The system may be vulnerable.
+ 
+ 	spectre_v2=	[X86] Control mitigation of Spectre variant 2
+ 			(indirect branch speculation) vulnerability.