From 1755c4b0372a2cf1e7124956b8cfebcb51083208 Mon Sep 17 00:00:00 2001 From: Tudor Ambarus Date: Tue, 9 Jan 2024 11:49:06 +0000 Subject: dt-bindings: clock: gs101: rename cmu_misc clock-names 'bus' and 'ip' are sufficient because naming is local to the module. As the bindings have not made a release yet, rename the cmu_misc clock-names. Fixes: 0a910f160638 ("dt-bindings: clock: Add Google gs101 clock management unit bindings") Suggested-by: Rob Herring Signed-off-by: Tudor Ambarus Reviewed-by: Sam Protsenko Acked-by: Rob Herring Link: https://lore.kernel.org/r/20240109114908.3623645-2-tudor.ambarus@linaro.org Signed-off-by: Krzysztof Kozlowski --- Documentation/devicetree/bindings/clock/google,gs101-clock.yaml | 4 ++-- 1 file changed, 2 insertions(+), 2 deletions(-) (limited to 'Documentation') diff --git a/Documentation/devicetree/bindings/clock/google,gs101-clock.yaml b/Documentation/devicetree/bindings/clock/google,gs101-clock.yaml index 3eebc03a309b..ca7fdada3ff2 100644 --- a/Documentation/devicetree/bindings/clock/google,gs101-clock.yaml +++ b/Documentation/devicetree/bindings/clock/google,gs101-clock.yaml @@ -85,8 +85,8 @@ allOf: clock-names: items: - - const: dout_cmu_misc_bus - - const: dout_cmu_misc_sss + - const: bus + - const: sss additionalProperties: false -- cgit v1.2.3 From 6613d82e617dd7eb8b0c40b2fe3acea655b1d611 Mon Sep 17 00:00:00 2001 From: Pawan Gupta Date: Tue, 13 Feb 2024 18:22:24 -0800 Subject: x86/bugs: Use ALTERNATIVE() instead of mds_user_clear static key The VERW mitigation at exit-to-user is enabled via a static branch mds_user_clear. This static branch is never toggled after boot, and can be safely replaced with an ALTERNATIVE() which is convenient to use in asm. Switch to ALTERNATIVE() to use the VERW mitigation late in exit-to-user path. Also remove the now redundant VERW in exc_nmi() and arch_exit_to_user_mode(). Signed-off-by: Pawan Gupta Signed-off-by: Dave Hansen Link: https://lore.kernel.org/all/20240213-delay-verw-v8-4-a6216d83edb7%40linux.intel.com --- Documentation/arch/x86/mds.rst | 38 +++++++++++++++++++++++++----------- arch/x86/include/asm/entry-common.h | 1 - arch/x86/include/asm/nospec-branch.h | 12 ------------ arch/x86/kernel/cpu/bugs.c | 15 ++++++-------- arch/x86/kernel/nmi.c | 3 --- arch/x86/kvm/vmx/vmx.c | 2 +- 6 files changed, 34 insertions(+), 37 deletions(-) (limited to 'Documentation') diff --git a/Documentation/arch/x86/mds.rst b/Documentation/arch/x86/mds.rst index e73fdff62c0a..c58c72362911 100644 --- a/Documentation/arch/x86/mds.rst +++ b/Documentation/arch/x86/mds.rst @@ -95,6 +95,9 @@ The kernel provides a function to invoke the buffer clearing: mds_clear_cpu_buffers() +Also macro CLEAR_CPU_BUFFERS can be used in ASM late in exit-to-user path. +Other than CFLAGS.ZF, this macro doesn't clobber any registers. + The mitigation is invoked on kernel/userspace, hypervisor/guest and C-state (idle) transitions. @@ -138,17 +141,30 @@ Mitigation points When transitioning from kernel to user space the CPU buffers are flushed on affected CPUs when the mitigation is not disabled on the kernel - command line. The migitation is enabled through the static key - mds_user_clear. - - The mitigation is invoked in prepare_exit_to_usermode() which covers - all but one of the kernel to user space transitions. The exception - is when we return from a Non Maskable Interrupt (NMI), which is - handled directly in do_nmi(). - - (The reason that NMI is special is that prepare_exit_to_usermode() can - enable IRQs. In NMI context, NMIs are blocked, and we don't want to - enable IRQs with NMIs blocked.) + command line. The mitigation is enabled through the feature flag + X86_FEATURE_CLEAR_CPU_BUF. + + The mitigation is invoked just before transitioning to userspace after + user registers are restored. This is done to minimize the window in + which kernel data could be accessed after VERW e.g. via an NMI after + VERW. + + **Corner case not handled** + Interrupts returning to kernel don't clear CPUs buffers since the + exit-to-user path is expected to do that anyways. But, there could be + a case when an NMI is generated in kernel after the exit-to-user path + has cleared the buffers. This case is not handled and NMI returning to + kernel don't clear CPU buffers because: + + 1. It is rare to get an NMI after VERW, but before returning to userspace. + 2. For an unprivileged user, there is no known way to make that NMI + less rare or target it. + 3. It would take a large number of these precisely-timed NMIs to mount + an actual attack. There's presumably not enough bandwidth. + 4. The NMI in question occurs after a VERW, i.e. when user state is + restored and most interesting data is already scrubbed. Whats left + is only the data that NMI touches, and that may or may not be of + any interest. 2. C-State transition diff --git a/arch/x86/include/asm/entry-common.h b/arch/x86/include/asm/entry-common.h index ce8f50192ae3..7e523bb3d2d3 100644 --- a/arch/x86/include/asm/entry-common.h +++ b/arch/x86/include/asm/entry-common.h @@ -91,7 +91,6 @@ static inline void arch_exit_to_user_mode_prepare(struct pt_regs *regs, static __always_inline void arch_exit_to_user_mode(void) { - mds_user_clear_cpu_buffers(); amd_clear_divider(); } #define arch_exit_to_user_mode arch_exit_to_user_mode diff --git a/arch/x86/include/asm/nospec-branch.h b/arch/x86/include/asm/nospec-branch.h index 077083ec81cb..2aa52cab1e46 100644 --- a/arch/x86/include/asm/nospec-branch.h +++ b/arch/x86/include/asm/nospec-branch.h @@ -540,7 +540,6 @@ DECLARE_STATIC_KEY_FALSE(switch_to_cond_stibp); DECLARE_STATIC_KEY_FALSE(switch_mm_cond_ibpb); DECLARE_STATIC_KEY_FALSE(switch_mm_always_ibpb); -DECLARE_STATIC_KEY_FALSE(mds_user_clear); DECLARE_STATIC_KEY_FALSE(mds_idle_clear); DECLARE_STATIC_KEY_FALSE(switch_mm_cond_l1d_flush); @@ -574,17 +573,6 @@ static __always_inline void mds_clear_cpu_buffers(void) asm volatile("verw %[ds]" : : [ds] "m" (ds) : "cc"); } -/** - * mds_user_clear_cpu_buffers - Mitigation for MDS and TAA vulnerability - * - * Clear CPU buffers if the corresponding static key is enabled - */ -static __always_inline void mds_user_clear_cpu_buffers(void) -{ - if (static_branch_likely(&mds_user_clear)) - mds_clear_cpu_buffers(); -} - /** * mds_idle_clear_cpu_buffers - Mitigation for MDS vulnerability * diff --git a/arch/x86/kernel/cpu/bugs.c b/arch/x86/kernel/cpu/bugs.c index bb0ab8466b91..48d049cd74e7 100644 --- a/arch/x86/kernel/cpu/bugs.c +++ b/arch/x86/kernel/cpu/bugs.c @@ -111,9 +111,6 @@ DEFINE_STATIC_KEY_FALSE(switch_mm_cond_ibpb); /* Control unconditional IBPB in switch_mm() */ DEFINE_STATIC_KEY_FALSE(switch_mm_always_ibpb); -/* Control MDS CPU buffer clear before returning to user space */ -DEFINE_STATIC_KEY_FALSE(mds_user_clear); -EXPORT_SYMBOL_GPL(mds_user_clear); /* Control MDS CPU buffer clear before idling (halt, mwait) */ DEFINE_STATIC_KEY_FALSE(mds_idle_clear); EXPORT_SYMBOL_GPL(mds_idle_clear); @@ -252,7 +249,7 @@ static void __init mds_select_mitigation(void) if (!boot_cpu_has(X86_FEATURE_MD_CLEAR)) mds_mitigation = MDS_MITIGATION_VMWERV; - static_branch_enable(&mds_user_clear); + setup_force_cpu_cap(X86_FEATURE_CLEAR_CPU_BUF); if (!boot_cpu_has(X86_BUG_MSBDS_ONLY) && (mds_nosmt || cpu_mitigations_auto_nosmt())) @@ -356,7 +353,7 @@ static void __init taa_select_mitigation(void) * For guests that can't determine whether the correct microcode is * present on host, enable the mitigation for UCODE_NEEDED as well. */ - static_branch_enable(&mds_user_clear); + setup_force_cpu_cap(X86_FEATURE_CLEAR_CPU_BUF); if (taa_nosmt || cpu_mitigations_auto_nosmt()) cpu_smt_disable(false); @@ -424,7 +421,7 @@ static void __init mmio_select_mitigation(void) */ if (boot_cpu_has_bug(X86_BUG_MDS) || (boot_cpu_has_bug(X86_BUG_TAA) && boot_cpu_has(X86_FEATURE_RTM))) - static_branch_enable(&mds_user_clear); + setup_force_cpu_cap(X86_FEATURE_CLEAR_CPU_BUF); else static_branch_enable(&mmio_stale_data_clear); @@ -484,12 +481,12 @@ static void __init md_clear_update_mitigation(void) if (cpu_mitigations_off()) return; - if (!static_key_enabled(&mds_user_clear)) + if (!boot_cpu_has(X86_FEATURE_CLEAR_CPU_BUF)) goto out; /* - * mds_user_clear is now enabled. Update MDS, TAA and MMIO Stale Data - * mitigation, if necessary. + * X86_FEATURE_CLEAR_CPU_BUF is now enabled. Update MDS, TAA and MMIO + * Stale Data mitigation, if necessary. */ if (mds_mitigation == MDS_MITIGATION_OFF && boot_cpu_has_bug(X86_BUG_MDS)) { diff --git a/arch/x86/kernel/nmi.c b/arch/x86/kernel/nmi.c index 17e955ab69fe..3082cf24b69e 100644 --- a/arch/x86/kernel/nmi.c +++ b/arch/x86/kernel/nmi.c @@ -563,9 +563,6 @@ nmi_restart: } if (this_cpu_dec_return(nmi_state)) goto nmi_restart; - - if (user_mode(regs)) - mds_user_clear_cpu_buffers(); } #if IS_ENABLED(CONFIG_KVM_INTEL) diff --git a/arch/x86/kvm/vmx/vmx.c b/arch/x86/kvm/vmx/vmx.c index 1111d9d08903..db8a5fe7edf6 100644 --- a/arch/x86/kvm/vmx/vmx.c +++ b/arch/x86/kvm/vmx/vmx.c @@ -7227,7 +7227,7 @@ static noinstr void vmx_vcpu_enter_exit(struct kvm_vcpu *vcpu, /* L1D Flush includes CPU buffer clear to mitigate MDS */ if (static_branch_unlikely(&vmx_l1d_should_flush)) vmx_l1d_flush(vcpu); - else if (static_branch_unlikely(&mds_user_clear)) + else if (cpu_feature_enabled(X86_FEATURE_CLEAR_CPU_BUF)) mds_clear_cpu_buffers(); else if (static_branch_unlikely(&mmio_stale_data_clear) && kvm_arch_has_assigned_device(vcpu->kvm)) -- cgit v1.2.3 From 23f9c2c066e7e5052406fb8f04a115d3d0260b22 Mon Sep 17 00:00:00 2001 From: Jakub Kicinski Date: Fri, 16 Feb 2024 08:19:45 -0800 Subject: docs: netdev: update the link to the CI repo Netronome graciously transferred the original NIPA repo to our new netdev umbrella org. Link to that instead of my private fork. Signed-off-by: Jakub Kicinski Reviewed-by: Simon Horman Link: https://lore.kernel.org/r/20240216161945.2208842-1-kuba@kernel.org Signed-off-by: Paolo Abeni --- Documentation/process/maintainer-netdev.rst | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-) (limited to 'Documentation') diff --git a/Documentation/process/maintainer-netdev.rst b/Documentation/process/maintainer-netdev.rst index 84ee60fceef2..fd96e4a3cef9 100644 --- a/Documentation/process/maintainer-netdev.rst +++ b/Documentation/process/maintainer-netdev.rst @@ -431,7 +431,7 @@ patchwork checks Checks in patchwork are mostly simple wrappers around existing kernel scripts, the sources are available at: -https://github.com/kuba-moo/nipa/tree/master/tests +https://github.com/linux-netdev/nipa/tree/master/tests **Do not** post your patches just to run them through the checks. You must ensure that your patches are ready by testing them locally -- cgit v1.2.3 From 0df8669f69a8638f04c6a3d1f3b7056c2c18f62c Mon Sep 17 00:00:00 2001 From: Jonathan Corbet Date: Mon, 19 Feb 2024 09:05:38 -0700 Subject: docs: Instruct LaTeX to cope with deeper nesting The addition of the XFS online fsck documentation starting with commit a8f6c2e54ddc ("xfs: document the motivation for online fsck design") added a deeper level of nesting than LaTeX is prepared to deal with. That caused a pdfdocs build failure with the helpful "Too deeply nested" error message buried deeply in Documentation/output/filesystems.log. Increase the "maxlistdepth" parameter to instruct LaTeX that it needs to deal with the deeper nesting whether it wants to or not. Suggested-by: Akira Yokosawa Tested-by: Akira Yokosawa Cc: stable@vger.kernel.org # v6.4+ Link: https://lore.kernel.org/linux-doc/67f6ac60-7957-4b92-9d72-a08fbad0e028@gmail.com/ Signed-off-by: Jonathan Corbet --- Documentation/conf.py | 6 ++++++ 1 file changed, 6 insertions(+) (limited to 'Documentation') diff --git a/Documentation/conf.py b/Documentation/conf.py index 5830b01c5642..da64c9fb7e07 100644 --- a/Documentation/conf.py +++ b/Documentation/conf.py @@ -388,6 +388,12 @@ latex_elements = { verbatimhintsturnover=false, ''', + # + # Some of our authors are fond of deep nesting; tell latex to + # cope. + # + 'maxlistdepth': '10', + # For CJK One-half spacing, need to be in front of hyperref 'extrapackages': r'\usepackage{setspace}', -- cgit v1.2.3 From b7b2ffc3ca59b06397550f96febe95f3f153eb1e Mon Sep 17 00:00:00 2001 From: Vegard Nossum Date: Thu, 15 Feb 2024 07:41:09 +0100 Subject: docs: translations: use attribute to store current language Akira Yokosawa reported [1] that the "translations" extension we added in commit 7418ec5b151f ("docs: translations: add translations links when they exist") broke the build on Sphinx versions v6.1.3 through 7.1.2 (possibly others) with the following error: Exception occurred: File "/usr/lib/python3.12/site-packages/sphinx/util/nodes.py", line 624, in _copy_except__document newnode = self.__class__(rawsource=self.rawsource, **self.attributes) ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^ TypeError: LanguagesNode.__init__() missing 1 required positional argument: 'current_language' The full traceback has been saved in /tmp/sphinx-err-7xmwytuu.log, if you want to report the issue to the developers. Solve this problem by making 'current_language' a true element attribute of the LanguagesNode element, which is probably the more correct way to do it anyway. Tested on Sphinx 2.x, 3.x, 6.x, and 7.x. [1]: https://lore.kernel.org/all/54a56c2e-a27c-45a0-b712-02a7bc7d2673@gmail.com/ Fixes: 7418ec5b151f ("docs: translations: add translations links when they exist") Reported-by: Akira Yokosawa Signed-off-by: Vegard Nossum Closes: https://lore.kernel.org/all/54a56c2e-a27c-45a0-b712-02a7bc7d2673@gmail.com/ Tested-by: Akira Yokosawa # Sphinx 4.3.2, 5.3.0 and 6.2.1 Signed-off-by: Jonathan Corbet Link: https://lore.kernel.org/r/20240215064109.1193556-1-vegard.nossum@oracle.com --- Documentation/sphinx/translations.py | 10 ++++------ 1 file changed, 4 insertions(+), 6 deletions(-) (limited to 'Documentation') diff --git a/Documentation/sphinx/translations.py b/Documentation/sphinx/translations.py index 47161e6eba99..32c2b32b2b5e 100644 --- a/Documentation/sphinx/translations.py +++ b/Documentation/sphinx/translations.py @@ -29,10 +29,7 @@ all_languages = { } class LanguagesNode(nodes.Element): - def __init__(self, current_language, *args, **kwargs): - super().__init__(*args, **kwargs) - - self.current_language = current_language + pass class TranslationsTransform(Transform): default_priority = 900 @@ -49,7 +46,8 @@ class TranslationsTransform(Transform): # normalize docname to be the untranslated one docname = os.path.join(*components[2:]) - new_nodes = LanguagesNode(all_languages[this_lang_code]) + new_nodes = LanguagesNode() + new_nodes['current_language'] = all_languages[this_lang_code] for lang_code, lang_name in all_languages.items(): if lang_code == this_lang_code: @@ -84,7 +82,7 @@ def process_languages(app, doctree, docname): html_content = app.builder.templates.render('translations.html', context={ - 'current_language': node.current_language, + 'current_language': node['current_language'], 'languages': languages, }) -- cgit v1.2.3