kernel.git/arch/riscv/kernel/setup.c, branch linux-5.13.y

riscv: Fix a number of free'd resources in init_resources()

2021-08-26T12:35:18Z

[ Upstream commit aa3e1ba32e553e611a58145c2eb349802feaa6eb ] Function init_resources() allocates a boot memory block to hold an array of resources which it adds to iomem_resource. The array is filled in from its end and the function then attempts to free any unused memory at the beginning. The problem is that size of the unused memory is incorrectly calculated and this can result in releasing memory which is in use by active resources. Their data then gets corrupted later when the memory is reused by a different part of the system. Fix the size of the released memory to correctly match the number of unused resource entries. Fixes: ffe0e5261268 ("RISC-V: Improve init_resources()") Signed-off-by: Petr Pavlu Reviewed-by: Sunil V L Acked-by: Nick Kossifidis Tested-by: Sunil V L Cc: stable@vger.kernel.org Signed-off-by: Palmer Dabbelt Signed-off-by: Sasha Levin

RISC-V: Fix memblock_free() usages in init_resources()

2021-06-02T04:16:42Z

`memblock_free()` takes a physical address as its first argument. Fix the wrong usages in `init_resources()`. Fixes: ffe0e526126884cf036a6f724220f1f9b4094fd2 ("RISC-V: Improve init_resources()") Fixes: 797f0375dd2ef5cdc68ac23450cbae9a5c67a74e ("RISC-V: Do not allocate memblock while iterating reserved memblocks") Signed-off-by: Wende Tan Signed-off-by: Palmer Dabbelt

riscv: Consistify protect_kernel_linear_mapping_text_rodata() use

2021-05-06T16:40:15Z

The various uses of protect_kernel_linear_mapping_text_rodata() are not consistent: - Its definition depends on "64BIT && !XIP_KERNEL", - Its forward declaration depends on MMU, - Its single caller depends on "STRICT_KERNEL_RWX && 64BIT && MMU && !XIP_KERNEL". Fix this by settling on the dependencies of the caller, which can be simplified as STRICT_KERNEL_RWX depends on "MMU && !XIP_KERNEL". Provide a dummy definition, as the caller is protected by "IS_ENABLED(CONFIG_STRICT_KERNEL_RWX)" instead of "#ifdef CONFIG_STRICT_KERNEL_RWX". Signed-off-by: Geert Uytterhoeven Tested-by: Alexandre Ghiti Signed-off-by: Palmer Dabbelt

RISC-V: enable XIP

2021-04-26T15:31:28Z

Introduce XIP (eXecute In Place) support for RISC-V platforms. It allows code to be executed directly from non-volatile storage directly addressable by the CPU, such as QSPI NOR flash which can be found on many RISC-V platforms. This makes way for significant optimization of RAM footprint. The XIP kernel is not compressed since it has to run directly from flash, so it will occupy more space on the non-volatile storage. The physical flash address used to link the kernel object files and for storing it has to be known at compile time and is represented by a Kconfig option. XIP on RISC-V will for the time being only work on MMU-enabled kernels. Signed-off-by: Vitaly Wool [Alex: Rebase on top of "Move kernel mapping outside the linear mapping" ] Signed-off-by: Alexandre Ghiti [Palmer: disable XIP for allyesconfig] Signed-off-by: Palmer Dabbelt

RISC-V: Add crash kernel support

2021-04-26T15:25:24Z

This patch allows Linux to act as a crash kernel for use with kdump. Userspace will let the crash kernel know about the memory region it can use through linux,usable-memory property on the /memory node (overriding its reg property), and about the memory region where the elf core header of the previous kernel is saved, through a reserved-memory node with a compatible string of "linux,elfcorehdr". This approach is the least invasive and re-uses functionality already present. I tested this on riscv64 qemu and it works as expected, you may test it by retrieving the dmesg of the previous kernel through /proc/vmcore, using the vmcore-dmesg utility from kexec-tools. Signed-off-by: Nick Kossifidis Signed-off-by: Palmer Dabbelt

RISC-V: Add kdump support

2021-04-26T15:25:23Z

This patch adds support for kdump, the kernel will reserve a region for the crash kernel and jump there on panic. In order for userspace tools (kexec-tools) to prepare the crash kernel kexec image, we also need to expose some information on /proc/iomem for the memory regions used by the kernel and for the region reserved for crash kernel. Note that on userspace the device tree is used to determine the system's memory layout so the "System RAM" on /proc/iomem is ignored. I tested this on riscv64 qemu and works as expected, you may test it by triggering a crash through /proc/sysrq_trigger: echo c > /proc/sysrq_trigger Signed-off-by: Nick Kossifidis Signed-off-by: Palmer Dabbelt

RISC-V: Improve init_resources()

2021-04-26T15:25:22Z

The kernel region is always present and we know where it is, no need to look for it inside the loop, just ignore it like the rest of the reserved regions within system's memory. Additionally, we don't need to call memblock_free inside the loop, as if called it'll split the region of pre-allocated resources in two parts, messing things up, just re-use the previous pre-allocated resource and free any unused resources after both loops finish. Signed-off-by: Nick Kossifidis [Palmer: commit text] Signed-off-by: Palmer Dabbelt

riscv: Move kernel mapping outside of linear mapping

2021-04-26T15:25:04Z

This is a preparatory patch for relocatable kernel and sv48 support. The kernel used to be linked at PAGE_OFFSET address therefore we could use the linear mapping for the kernel mapping. But the relocated kernel base address will be different from PAGE_OFFSET and since in the linear mapping, two different virtual addresses cannot point to the same physical address, the kernel mapping needs to lie outside the linear mapping so that we don't have to copy it at the same physical offset. The kernel mapping is moved to the last 2GB of the address space, BPF is now always after the kernel and modules use the 2GB memory range right before the kernel, so BPF and modules regions do not overlap. KASLR implementation will simply have to move the kernel in the last 2GB range and just take care of leaving enough space for BPF. In addition, by moving the kernel to the end of the address space, both sv39 and sv48 kernels will be exactly the same without needing to be relocated at runtime. Suggested-by: Arnd Bergmann Signed-off-by: Alexandre Ghiti [Palmer: Squash the STRICT_RWX fix, and a !MMU fix] Signed-off-by: Palmer Dabbelt

Merge tag 'riscv-for-linus-5.12-mw0' of git://git.kernel.org/pub/scm/linux/kernel/git/riscv/linux

2021-02-26T18:28:35Z

Pull RISC-V updates from Palmer Dabbelt: "A handful of new RISC-V related patches for this merge window: - A check to ensure drivers are properly using uaccess. This isn't manifesting with any of the drivers I'm currently using, but may catch errors in new drivers. - Some preliminary support for the FU740, along with the HiFive Unleashed it will appear on. - NUMA support for RISC-V, which involves making the arm64 code generic. - Support for kasan on the vmalloc region. - A handful of new drivers for the Kendryte K210, along with the DT plumbing required to boot on a handful of K210-based boards. - Support for allocating ASIDs. - Preliminary support for kernels larger than 128MiB. - Various other improvements to our KASAN support, including the utilization of huge pages when allocating the KASAN regions. We may have already found a bug with the KASAN_VMALLOC code, but it's passing my tests. There's a fix in the works, but that will probably miss the merge window. * tag 'riscv-for-linus-5.12-mw0' of git://git.kernel.org/pub/scm/linux/kernel/git/riscv/linux: (75 commits) riscv: Improve kasan population by using hugepages when possible riscv: Improve kasan population function riscv: Use KASAN_SHADOW_INIT define for kasan memory initialization riscv: Improve kasan definitions riscv: Get rid of MAX_EARLY_MAPPING_SIZE soc: canaan: Sort the Makefile alphabetically riscv: Disable KSAN_SANITIZE for vDSO riscv: Remove unnecessary declaration riscv: Add Canaan Kendryte K210 SD card defconfig riscv: Update Canaan Kendryte K210 defconfig riscv: Add Kendryte KD233 board device tree riscv: Add SiPeed MAIXDUINO board device tree riscv: Add SiPeed MAIX GO board device tree riscv: Add SiPeed MAIX DOCK board device tree riscv: Add SiPeed MAIX BiT board device tree riscv: Update Canaan Kendryte K210 device tree dt-bindings: add resets property to dw-apb-timer dt-bindings: fix sifive gpio properties dt-bindings: update sifive uart compatible string dt-bindings: update sifive clint compatible string ...

RISC-V: Fix .init section permission update

2021-02-03T02:35:42Z

.init section permission should only updated to non-execute if STRICT_KERNEL_RWX is enabled. Otherwise, this will lead to a kernel hang. Fixes: 19a00869028f ("RISC-V: Protect all kernel sections including init early") Cc: stable@vger.kernel.org Suggested-by: Geert Uytterhoeven Reported-by: Geert Uytterhoeven Signed-off-by: Atish Patra Reviewed-by: Atish Patra Signed-off-by: Palmer Dabbelt