kernel/git/stable/linux.git/arch/arm/include, branch linux-5.18.y

ARM: 9216/1: Fix MAX_DMA_ADDRESS overflow

2022-08-03T10:05:29+00:00

[ Upstream commit fb0fd3469ead5b937293c213daa1f589b4b7ce46 ] Commit 26f09e9b3a06 ("mm/memblock: add memblock memory allocation apis") added a check to determine whether arm_dma_zone_size is exceeding the amount of kernel virtual address space available between the upper 4GB virtual address limit and PAGE_OFFSET in order to provide a suitable definition of MAX_DMA_ADDRESS that should fit within the 32-bit virtual address space. The quantity used for comparison was off by a missing trailing 0, leading to MAX_DMA_ADDRESS to be overflowing a 32-bit quantity. This was caught thanks to CONFIG_DEBUG_VIRTUAL on the bcm2711 platform where we define a dma_zone_size of 1GB and we have a PAGE_OFFSET value of 0xc000_0000 (CONFIG_VMSPLIT_3G) leading to MAX_DMA_ADDRESS being 0x1_0000_0000 which overflows the unsigned long type used throughout __pa() and then __virt_addr_valid(). Because the virtual address passed to __virt_addr_valid() would now be 0, the function would loudly warn and flood the kernel log, thus making the platform unable to boot properly. Fixes: 26f09e9b3a06 ("mm/memblock: add memblock memory allocation apis") Signed-off-by: Florian Fainelli Reviewed-by: Linus Walleij Signed-off-by: Russell King (Oracle) Signed-off-by: Sasha Levin

ARM: 9211/1: domain: drop modify_domain()

2022-07-22T08:21:44+00:00

[ Upstream commit cc45b836388f0ccc6831288a08f77a33845f10b0 ] This function/macro isn't used anywhere in the kernel. The only user was set_fs() and was deleted in the set_fs() removal patch set. Fixes: 8ac6f5d7f84b ("ARM: 9113/1: uaccess: remove set_fs() implementation") Acked-by: Arnd Bergmann Signed-off-by: Linus Walleij Signed-off-by: Russell King (Oracle) Signed-off-by: Sasha Levin

ARM: 9210/1: Mark the FDT_FIXED sections as shareable

2022-07-22T08:21:23+00:00

[ Upstream commit 598f0a99fa8a35be44b27106b43ddc66417af3b1 ] commit 7a1be318f579 ("ARM: 9012/1: move device tree mapping out of linear region") use FDT_FIXED_BASE to map the whole FDT_FIXED_SIZE memory area which contains fdt. But it only reserves the exact physical memory that fdt occupied. Unfortunately, this mapping is non-shareable. An illegal or speculative read access can bring the RAM content from non-fdt zone into cache, PIPT makes it to be hit by subsequently read access through shareable mapping(such as linear mapping), and the cache consistency between cores is lost due to non-shareable property. |<---------FDT_FIXED_SIZE------>| | | ------------------------------- | | | | ------------------------------- 1. CoreA read through MT_ROM mapping, the old data is loaded into the cache. 2. CoreB write to update data through linear mapping. CoreA received the notification to invalid the corresponding cachelines, but the property non-shareable makes it to be ignored. 3. CoreA read through linear mapping, cache hit, the old data is read. To eliminate this risk, add a new memory type MT_MEMORY_RO. Compared to MT_ROM, it is shareable and non-executable. Here's an example: list_del corruption. prev->next should be c0ecbf74, but was c08410dc kernel BUG at lib/list_debug.c:53! ... ... PC is at __list_del_entry_valid+0x58/0x98 LR is at __list_del_entry_valid+0x58/0x98 psr: 60000093 sp : c0ecbf30 ip : 00000000 fp : 00000001 r10: c08410d0 r9 : 00000001 r8 : c0825e0c r7 : 20000013 r6 : c08410d0 r5 : c0ecbf74 r4 : c0ecbf74 r3 : c0825d08 r2 : 00000000 r1 : df7ce6f4 r0 : 00000044 ... ... Stack: (0xc0ecbf30 to 0xc0ecc000) bf20: c0ecbf74 c0164fd0 c0ecbf70 c0165170 bf40: c0eca000 c0840c00 c0840c00 c0824500 c0825e0c c0189bbc c088f404 60000013 bf60: 60000013 c0e85100 000004ec 00000000 c0ebcdc0 c0ecbf74 c0ecbf74 c0825d08 ... ... < next prev > (__list_del_entry_valid) from (__list_del_entry+0xc/0x20) (__list_del_entry) from (finish_swait+0x60/0x7c) (finish_swait) from (rcu_gp_kthread+0x560/0xa20) (rcu_gp_kthread) from (kthread+0x14c/0x15c) (kthread) from (ret_from_fork+0x14/0x24) The faulty list node to be deleted is a local variable, its address is c0ecbf74. The dumped stack shows that 'prev' = c0ecbf74, but its value before lib/list_debug.c:53 is c08410dc. A large amount of printing results in swapping out the cacheline containing the old data(MT_ROM mapping is read only, so the cacheline cannot be dirty), and the subsequent dump operation obtains new data from the DDR. Fixes: 7a1be318f579 ("ARM: 9012/1: move device tree mapping out of linear region") Suggested-by: Ard Biesheuvel Signed-off-by: Zhen Lei Reviewed-by: Ard Biesheuvel Reviewed-by: Kefeng Wang Signed-off-by: Russell King (Oracle) Signed-off-by: Sasha Levin

ARM: 9214/1: alignment: advance IT state after emulating Thumb instruction

2022-07-22T08:21:20+00:00

commit e5c46fde75e43c15a29b40e5fc5641727f97ae47 upstream. After emulating a misaligned load or store issued in Thumb mode, we have to advance the IT state by hand, or it will get out of sync with the actual instruction stream, which means we'll end up applying the wrong condition code to subsequent instructions. This might corrupt the program state rather catastrophically. So borrow the it_advance() helper from the probing code, and use it on CPSR if the emulated instruction is Thumb. Cc: Reviewed-by: Linus Walleij Signed-off-by: Ard Biesheuvel Signed-off-by: Russell King (Oracle) Signed-off-by: Greg Kroah-Hartman

irqchip/gic-v3: Refactor ISB + EOIR at ack time

2022-06-09T08:30:14+00:00

[ Upstream commit 6efb50923771f392122f5ce69dfc43b08f16e449 ] There are cases where a context synchronization event is necessary between an IRQ being raised and being handled, and there are races such that we cannot rely upon the exception entry being subsequent to the interrupt being raised. To fix this, we place an ISB between a read of IAR and the subsequent invocation of an IRQ handler. When EOI mode 1 is in use, we need to EOI an interrupt prior to invoking its handler, and we have a write to EOIR for this. As this write to EOIR requires an ISB, and this is provided by the gic_write_eoir() helper, we omit the usual ISB in this case, with the logic being: | if (static_branch_likely(&supports_deactivate_key)) | gic_write_eoir(irqnr); | else | isb(); This is somewhat opaque, and it would be a little clearer if there were an unconditional ISB, with only the write to EOIR being conditional, e.g. | if (static_branch_likely(&supports_deactivate_key)) | write_gicreg(irqnr, ICC_EOIR1_EL1); | | isb(); This patch rewrites the code that way, with this logic factored into a new helper function with comments explaining what the ISB is for, as were originally laid out in commit: 39a06b67c2c1256b ("irqchip/gic: Ensure we have an ISB between ack and ->handle_irq") Note that since then, we removed the IAR polling in commit: 342677d70ab92142 ("irqchip/gic-v3: Remove acknowledge loop") ... which removed one of the two race conditions. For consistency, other portions of the driver are made to manipulate EOIR using write_gicreg() and explcit ISBs, and the gic_write_eoir() helper function is removed. There should be no functional change as a result of this patch. Signed-off-by: Mark Rutland Cc: Marc Zyngier Cc: Thomas Gleixner Cc: Will Deacon Signed-off-by: Marc Zyngier Link: https://lore.kernel.org/r/20220513133038.226182-3-mark.rutland@arm.com Signed-off-by: Sasha Levin

arm: use fallback for random_get_entropy() instead of zero

2022-05-30T07:24:05+00:00

commit ff8a8f59c99f6a7c656387addc4d9f2247d75077 upstream. In the event that random_get_entropy() can't access a cycle counter or similar, falling back to returning 0 is really not the best we can do. Instead, at least calling random_get_entropy_fallback() would be preferable, because that always needs to return _something_, even falling back to jiffies eventually. It's not as though random_get_entropy_fallback() is super high precision or guaranteed to be entropic, but basically anything that's not zero all the time is better than returning zero all the time. Cc: Thomas Gleixner Cc: Arnd Bergmann Reviewed-by: Russell King (Oracle) Signed-off-by: Jason A. Donenfeld Signed-off-by: Greg Kroah-Hartman

arm[64]/memremap: don't abuse pfn_valid() to ensure presence of linear map

2022-05-10T00:34:28+00:00

The semantics of pfn_valid() is to check presence of the memory map for a PFN and not whether a PFN is covered by the linear map. The memory map may be present for NOMAP memory regions, but they won't be mapped in the linear mapping. Accessing such regions via __va() when they are memremap()'ed will cause a crash. On v5.4.y the crash happens on qemu-arm with UEFI [1]: <1>[ 0.084476] 8<--- cut here --- <1>[ 0.084595] Unable to handle kernel paging request at virtual address dfb76000 <1>[ 0.084938] pgd = (ptrval) <1>[ 0.085038] [dfb76000] *pgd=5f7fe801, *pte=00000000, *ppte=00000000 ... <4>[ 0.093923] [] (memcpy) from [] (dmi_setup+0x60/0x418) <4>[ 0.094204] [] (dmi_setup) from [] (arm_dmi_init+0x8/0x10) <4>[ 0.094408] [] (arm_dmi_init) from [] (do_one_initcall+0x50/0x228) <4>[ 0.094619] [] (do_one_initcall) from [] (kernel_init_freeable+0x15c/0x1f8) <4>[ 0.094841] [] (kernel_init_freeable) from [] (kernel_init+0x8/0x10c) <4>[ 0.095057] [] (kernel_init) from [] (ret_from_fork+0x14/0x2c) On kernels v5.10.y and newer the same crash won't reproduce on ARM because commit b10d6bca8720 ("arch, drivers: replace for_each_membock() with for_each_mem_range()") changed the way memory regions are registered in the resource tree, but that merely covers up the problem. On ARM64 memory resources registered in yet another way and there the issue of wrong usage of pfn_valid() to ensure availability of the linear map is also covered. Implement arch_memremap_can_ram_remap() on ARM and ARM64 to prevent access to NOMAP regions via the linear mapping in memremap(). Link: https://lore.kernel.org/all/Yl65zxGgFzF1Okac@sirena.org.uk Link: https://lkml.kernel.org/r/20220426060107.7618-1-rppt@kernel.org Signed-off-by: Mike Rapoport Reported-by: "kernelci.org bot" Tested-by: Mark Brown Reviewed-by: Ard Biesheuvel Acked-by: Catalin Marinas Cc: Greg Kroah-Hartman Cc: Mark Brown Cc: Mark-PK Tsai Cc: Russell King Cc: Tony Lindgren Cc: Will Deacon Cc: [5.4+] Signed-off-by: Andrew Morton

Merge branch 'work.misc' of git://git.kernel.org/pub/scm/linux/kernel/git/viro/vfs

2022-04-02T02:57:03+00:00

Pull vfs updates from Al Viro: "Assorted bits and pieces" * 'work.misc' of git://git.kernel.org/pub/scm/linux/kernel/git/viro/vfs: aio: drop needless assignment in aio_read() clean overflow checks in count_mounts() a bit seq_file: fix NULL pointer arithmetic warning uml/x86: use x86 load_unaligned_zeropad() asm/user.h: killed unused macros constify struct path argument of finish_automount()/do_add_mount() fs: Remove FIXME comment in generic_write_checks()

Merge tag 'asm-generic-5.18' of git://git.kernel.org/pub/scm/linux/kernel/git/arnd/asm-generic

2022-03-24T01:03:08+00:00

Pull asm-generic updates from Arnd Bergmann: "There are three sets of updates for 5.18 in the asm-generic tree: - The set_fs()/get_fs() infrastructure gets removed for good. This was already gone from all major architectures, but now we can finally remove it everywhere, which loses some particularly tricky and error-prone code. There is a small merge conflict against a parisc cleanup, the solution is to use their new version. - The nds32 architecture ends its tenure in the Linux kernel. The hardware is still used and the code is in reasonable shape, but the mainline port is not actively maintained any more, as all remaining users are thought to run vendor kernels that would never be updated to a future release. - A series from Masahiro Yamada cleans up some of the uapi header files to pass the compile-time checks" * tag 'asm-generic-5.18' of git://git.kernel.org/pub/scm/linux/kernel/git/arnd/asm-generic: (27 commits) nds32: Remove the architecture uaccess: remove CONFIG_SET_FS ia64: remove CONFIG_SET_FS support sh: remove CONFIG_SET_FS support sparc64: remove CONFIG_SET_FS support lib/test_lockup: fix kernel pointer check for separate address spaces uaccess: generalize access_ok() uaccess: fix type mismatch warnings from access_ok() arm64: simplify access_ok() m68k: fix access_ok for coldfire MIPS: use simpler access_ok() MIPS: Handle address errors for accesses above CPU max virtual user address uaccess: add generic __{get,put}_kernel_nofault nios2: drop access_ok() check from __put_user() x86: use more conventional access_ok() definition x86: remove __range_not_ok() sparc64: add __{get,put}_kernel_nofault() nds32: fix access_ok() checks in get/put_user uaccess: fix nios2 and microblaze get_user_8() sparc64: fix building assembly files ...

Merge tag 'for-linus' of git://git.armlinux.org.uk/~rmk/linux-arm

2022-03-24T00:35:57+00:00

Pull ARM updates from Russell King: "Updates for IRQ stacks and virtually mapped stack support, and ftrace: - Support for IRQ and vmap'ed stacks This covers all the work related to implementing IRQ stacks and vmap'ed stacks for all 32-bit ARM systems that are currently supported by the Linux kernel, including RiscPC and Footbridge. It has been submitted for review in four different waves: - IRQ stacks support for v7 SMP systems [0] - vmap'ed stacks support for v7 SMP systems[1] - extending support for both IRQ stacks and vmap'ed stacks for all remaining configurations, including v6/v7 SMP multiplatform kernels and uniprocessor configurations including v7-M [2] - fixes and updates in [3] - ftrace fixes and cleanups Make all flavors of ftrace available on all builds, regardless of ISA choice, unwinder choice or compiler [4]: - use ADD not POP where possible - fix a couple of Thumb2 related issues - enable HAVE_FUNCTION_GRAPH_FP_TEST for robustness - enable the graph tracer with the EABI unwinder - avoid clobbering frame pointer registers to make Clang happy - Fixes for the above" [0] https://lore.kernel.org/linux-arm-kernel/20211115084732.3704393-1-ardb@kernel.org/ [1] https://lore.kernel.org/linux-arm-kernel/20211122092816.2865873-1-ardb@kernel.org/ [2] https://lore.kernel.org/linux-arm-kernel/20211206164659.1495084-1-ardb@kernel.org/ [3] https://lore.kernel.org/linux-arm-kernel/20220124174744.1054712-1-ardb@kernel.org/ [4] https://lore.kernel.org/linux-arm-kernel/20220203082204.1176734-1-ardb@kernel.org/ * tag 'for-linus' of git://git.armlinux.org.uk/~rmk/linux-arm: (62 commits) ARM: fix building NOMMU ARMv4/v5 kernels ARM: unwind: only permit stack switch when unwinding call_with_stack() ARM: Revert "unwind: dump exception stack from calling frame" ARM: entry: fix unwinder problems caused by IRQ stacks ARM: unwind: set frame.pc correctly for current-thread unwinding ARM: 9184/1: return_address: disable again for CONFIG_ARM_UNWIND=y ARM: 9183/1: unwind: avoid spurious warnings on bogus code addresses Revert "ARM: 9144/1: forbid ftrace with clang and thumb2_kernel" ARM: mach-bcm: disable ftrace in SMC invocation routines ARM: cacheflush: avoid clobbering the frame pointer ARM: kprobes: treat R7 as the frame pointer register in Thumb2 builds ARM: ftrace: enable the graph tracer with the EABI unwinder ARM: unwind: track location of LR value in stack frame ARM: ftrace: enable HAVE_FUNCTION_GRAPH_FP_TEST ARM: ftrace: avoid unnecessary literal loads ARM: ftrace: avoid redundant loads or clobbering IP ARM: ftrace: use trampolines to keep .init.text in branching range ARM: ftrace: use ADD not POP to counter PUSH at entry ARM: ftrace: ensure that ADR takes the Thumb bit into account ARM: make get_current() and __my_cpu_offset() __always_inline ...