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authorLinus Torvalds2024-05-13 08:33:52 -0700
committerLinus Torvalds2024-05-13 08:33:52 -0700
commitd65e1a0f305ba3e7aabf6261a37bb871790d9f93 (patch)
tree4033039381e4a35eb76158e5b5130f05ae204139 /Documentation
parenta38297e3fb012ddfa7ce0321a7e5a8daeb1872b6 (diff)
parent1812dc9c334f98227c65bc9c475f16fb6840a94b (diff)
Merge tag 's390-6.10-1' of git://git.kernel.org/pub/scm/linux/kernel/git/s390/linux
Pull s390 updates from Alexander Gordeev: - Store AP Query Configuration Information in a static buffer - Rework the AP initialization and add missing cleanups to the error path - Swap IRQ and AP bus/device registration to avoid race conditions - Export prot_virt_guest symbol - Introduce AP configuration changes notifier interface to facilitate modularization of the AP bus - Add CONFIG_AP kernel configuration option to allow modularization of the AP bus - Rework CONFIG_ZCRYPT_DEBUG kernel configuration option description and dependency and rename it to CONFIG_AP_DEBUG - Convert sprintf() and snprintf() to sysfs_emit() in CIO code - Adjust indentation of RELOCS command build step - Make crypto performance counters upward compatible - Convert make_page_secure() and gmap_make_secure() to use folio - Rework channel-utilization-block (CUB) handling in preparation of introducing additional CUBs - Use attribute groups to simplify registration, removal and extension of measurement-related channel-path sysfs attributes - Add a per-channel-path binary "ext_measurement" sysfs attribute that provides access to extended channel-path measurement data - Export measurement data for all channel-measurement-groups (CMG), not only for a specific ones. This enables support of new CMG data formats in userspace without the need for kernel changes - Add a per-channel-path sysfs attribute "speed_bps" that provides the operating speed in bits per second or 0 if the operating speed is not available - The CIO tracepoint subchannel-type field "st" is incorrectly set to the value of subchannel-enabled SCHIB "ena" field. Fix that - Do not forcefully limit vmemmap starting address to MAX_PHYSMEM_BITS - Consider the maximum physical address available to a DCSS segment (512GB) when memory layout is set up - Simplify the virtual memory layout setup by reducing the size of identity mapping vs vmemmap overlap - Swap vmalloc and Lowcore/Real Memory Copy areas in virtual memory. This will allow to place the kernel image next to kernel modules - Move everyting KASLR related from <asm/setup.h> to <asm/page.h> - Put virtual memory layout information into a structure to improve code generation - Currently __kaslr_offset is the kernel offset in both physical and virtual memory spaces. Uncouple these offsets to allow uncoupling of the addresses spaces - Currently the identity mapping base address is implicit and is always set to zero. Make it explicit by putting into __identity_base persistent boot variable and use it in proper context - Introduce .amode31 section start and end macros AMODE31_START and AMODE31_END - Introduce OS_INFO entries that do not reference any data in memory, but rather provide only values - Store virtual memory layout in OS_INFO. It is read out by makedumpfile, crash and other tools - Store virtual memory layout in VMCORE_INFO. It is read out by crash and other tools when /proc/kcore device is used - Create additional PT_LOAD ELF program header that covers kernel image only, so that vmcore tools could locate kernel text and data when virtual and physical memory spaces are uncoupled - Uncouple physical and virtual address spaces - Map kernel at fixed location when KASLR mode is disabled. The location is defined by CONFIG_KERNEL_IMAGE_BASE kernel configuration value. - Rework deployment of kernel image for both compressed and uncompressed variants as defined by CONFIG_KERNEL_UNCOMPRESSED kernel configuration value - Move .vmlinux.relocs section in front of the compressed kernel. The interim section rescue step is avoided as result - Correct modules thunk offset calculation when branch target is more than 2GB away - Kernel modules contain their own set of expoline thunks. Now that the kernel modules area is less than 4GB away from kernel expoline thunks, make modules use kernel expolines. Also make EXPOLINE_EXTERN the default if the compiler supports it - userfaultfd can insert shared zeropages into processes running VMs, but that is not allowed for s390. Fallback to allocating a fresh zeroed anonymous folio and insert that instead - Re-enable shared zeropages for non-PV and non-skeys KVM guests - Rename hex2bitmap() to ap_hex2bitmap() and export it for external use - Add ap_config sysfs attribute to provide the means for setting or displaying adapters, domains and control domains assigned to a vfio-ap mediated device in a single operation - Make vfio_ap_mdev_link_queue() ignore duplicate link requests - Add write support to ap_config sysfs attribute to allow atomic update a vfio-ap mediated device state - Document ap_config sysfs attribute - Function os_info_old_init() is expected to be called only from a regular kdump kernel. Enable it to be called from a stand-alone dump kernel - Address gcc -Warray-bounds warning and fix array size in struct os_info - s390 does not support SMBIOS, so drop unneeded CONFIG_DMI checks - Use unwinder instead of __builtin_return_address() with ftrace to prevent returning of undefined values - Sections .hash and .gnu.hash are only created when CONFIG_PIE_BUILD kernel is enabled. Drop these for the case CONFIG_PIE_BUILD is disabled - Compile kernel with -fPIC and link with -no-pie to allow kpatch feature always succeed and drop the whole CONFIG_PIE_BUILD option-enabled code - Add missing virt_to_phys() converter for VSIE facility and crypto control blocks * tag 's390-6.10-1' of git://git.kernel.org/pub/scm/linux/kernel/git/s390/linux: (54 commits) Revert "s390: Relocate vmlinux ELF data to virtual address space" KVM: s390: vsie: Use virt_to_phys for crypto control block s390: Relocate vmlinux ELF data to virtual address space s390: Compile kernel with -fPIC and link with -no-pie s390: vmlinux.lds.S: Drop .hash and .gnu.hash for !CONFIG_PIE_BUILD s390/ftrace: Use unwinder instead of __builtin_return_address() s390/pci: Drop unneeded reference to CONFIG_DMI s390/os_info: Fix array size in struct os_info s390/os_info: Initialize old os_info in standalone dump kernel docs: Update s390 vfio-ap doc for ap_config sysfs attribute s390/vfio-ap: Add write support to sysfs attr ap_config s390/vfio-ap: Ignore duplicate link requests in vfio_ap_mdev_link_queue s390/vfio-ap: Add sysfs attr, ap_config, to export mdev state s390/ap: Externalize AP bus specific bitmap reading function s390/mm: Re-enable the shared zeropage for !PV and !skeys KVM guests mm/userfaultfd: Do not place zeropages when zeropages are disallowed s390/expoline: Make modules use kernel expolines s390/nospec: Correct modules thunk offset calculation s390/boot: Do not rescue .vmlinux.relocs section s390/boot: Rework deployment of the kernel image ...
Diffstat (limited to 'Documentation')
-rw-r--r--Documentation/admin-guide/kernel-parameters.txt4
-rw-r--r--Documentation/arch/s390/index.rst1
-rw-r--r--Documentation/arch/s390/mm.rst111
-rw-r--r--Documentation/arch/s390/vfio-ap.rst32
4 files changed, 146 insertions, 2 deletions
diff --git a/Documentation/admin-guide/kernel-parameters.txt b/Documentation/admin-guide/kernel-parameters.txt
index 396137ee018d..535301f6dd09 100644
--- a/Documentation/admin-guide/kernel-parameters.txt
+++ b/Documentation/admin-guide/kernel-parameters.txt
@@ -4785,7 +4785,9 @@
prot_virt= [S390] enable hosting protected virtual machines
isolated from the hypervisor (if hardware supports
- that).
+ that). If enabled, the default kernel base address
+ might be overridden even when Kernel Address Space
+ Layout Randomization is disabled.
Format: <bool>
psi= [KNL] Enable or disable pressure stall information
diff --git a/Documentation/arch/s390/index.rst b/Documentation/arch/s390/index.rst
index 73c79bf586fd..e75a6e5d2505 100644
--- a/Documentation/arch/s390/index.rst
+++ b/Documentation/arch/s390/index.rst
@@ -8,6 +8,7 @@ s390 Architecture
cds
3270
driver-model
+ mm
monreader
qeth
s390dbf
diff --git a/Documentation/arch/s390/mm.rst b/Documentation/arch/s390/mm.rst
new file mode 100644
index 000000000000..084adad5eef9
--- /dev/null
+++ b/Documentation/arch/s390/mm.rst
@@ -0,0 +1,111 @@
+.. SPDX-License-Identifier: GPL-2.0
+
+=================
+Memory Management
+=================
+
+Virtual memory layout
+=====================
+
+.. note::
+
+ - Some aspects of the virtual memory layout setup are not
+ clarified (number of page levels, alignment, DMA memory).
+
+ - Unused gaps in the virtual memory layout could be present
+ or not - depending on how partucular system is configured.
+ No page tables are created for the unused gaps.
+
+ - The virtual memory regions are tracked or untracked by KASAN
+ instrumentation, as well as the KASAN shadow memory itself is
+ created only when CONFIG_KASAN configuration option is enabled.
+
+::
+
+ =============================================================================
+ | Physical | Virtual | VM area description
+ =============================================================================
+ +- 0 --------------+- 0 --------------+
+ | | S390_lowcore | Low-address memory
+ | +- 8 KB -----------+
+ | | |
+ | | |
+ | | ... unused gap | KASAN untracked
+ | | |
+ +- AMODE31_START --+- AMODE31_START --+ .amode31 rand. phys/virt start
+ |.amode31 text/data|.amode31 text/data| KASAN untracked
+ +- AMODE31_END ----+- AMODE31_END ----+ .amode31 rand. phys/virt end (<2GB)
+ | | |
+ | | |
+ +- __kaslr_offset_phys | kernel rand. phys start
+ | | |
+ | kernel text/data | |
+ | | |
+ +------------------+ | kernel phys end
+ | | |
+ | | |
+ | | |
+ | | |
+ +- ident_map_size -+ |
+ | |
+ | ... unused gap | KASAN untracked
+ | |
+ +- __identity_base + identity mapping start (>= 2GB)
+ | |
+ | identity | phys == virt - __identity_base
+ | mapping | virt == phys + __identity_base
+ | |
+ | | KASAN tracked
+ | |
+ | |
+ | |
+ | |
+ | |
+ | |
+ | |
+ | |
+ | |
+ | |
+ | |
+ | |
+ | |
+ | |
+ | |
+ +---- vmemmap -----+ 'struct page' array start
+ | |
+ | virtually mapped |
+ | memory map | KASAN untracked
+ | |
+ +- __abs_lowcore --+
+ | |
+ | Absolute Lowcore | KASAN untracked
+ | |
+ +- __memcpy_real_area
+ | |
+ | Real Memory Copy| KASAN untracked
+ | |
+ +- VMALLOC_START --+ vmalloc area start
+ | | KASAN untracked or
+ | vmalloc area | KASAN shallowly populated in case
+ | | CONFIG_KASAN_VMALLOC=y
+ +- MODULES_VADDR --+ modules area start
+ | | KASAN allocated per module or
+ | modules area | KASAN shallowly populated in case
+ | | CONFIG_KASAN_VMALLOC=y
+ +- __kaslr_offset -+ kernel rand. virt start
+ | | KASAN tracked
+ | kernel text/data | phys == (kvirt - __kaslr_offset) +
+ | | __kaslr_offset_phys
+ +- kernel .bss end + kernel rand. virt end
+ | |
+ | ... unused gap | KASAN untracked
+ | |
+ +------------------+ UltraVisor Secure Storage limit
+ | |
+ | ... unused gap | KASAN untracked
+ | |
+ +KASAN_SHADOW_START+ KASAN shadow memory start
+ | |
+ | KASAN shadow | KASAN untracked
+ | |
+ +------------------+ ASCE limit
diff --git a/Documentation/arch/s390/vfio-ap.rst b/Documentation/arch/s390/vfio-ap.rst
index 929ee1c1c940..ea744cbc8687 100644
--- a/Documentation/arch/s390/vfio-ap.rst
+++ b/Documentation/arch/s390/vfio-ap.rst
@@ -380,6 +380,36 @@ matrix device.
control_domains:
A read-only file for displaying the control domain numbers assigned to the
vfio_ap mediated device.
+ ap_config:
+ A read/write file that, when written to, allows all three of the
+ vfio_ap mediated device's ap matrix masks to be replaced in one shot.
+ Three masks are given, one for adapters, one for domains, and one for
+ control domains. If the given state cannot be set then no changes are
+ made to the vfio-ap mediated device.
+
+ The format of the data written to ap_config is as follows:
+ {amask},{dmask},{cmask}\n
+
+ \n is a newline character.
+
+ amask, dmask, and cmask are masks identifying which adapters, domains,
+ and control domains should be assigned to the mediated device.
+
+ The format of a mask is as follows:
+ 0xNN..NN
+
+ Where NN..NN is 64 hexadecimal characters representing a 256-bit value.
+ The leftmost (highest order) bit represents adapter/domain 0.
+
+ For an example set of masks that represent your mdev's current
+ configuration, simply cat ap_config.
+
+ Setting an adapter or domain number greater than the maximum allowed for
+ the system will result in an error.
+
+ This attribute is intended to be used by automation. End users would be
+ better served using the respective assign/unassign attributes for
+ adapters, domains, and control domains.
* functions:
@@ -550,7 +580,7 @@ These are the steps:
following Kconfig elements selected:
* IOMMU_SUPPORT
* S390
- * ZCRYPT
+ * AP
* VFIO
* KVM