From 251cc826be7dec61e574b291b371362c10dd84ea Mon Sep 17 00:00:00 2001 From: Masahiro Yamada Date: Sat, 30 Oct 2021 18:52:58 +0100 Subject: [PATCH 01/12] ARM: 9154/1: decompressor: do not copy source files while building As commit 7ae4a78daacf ("ARM: 8969/1: decompressor: simplify libfdt builds") stated, copying source files during the build time may not end up with as clean code as expected. Do similar for the other library files for further cleanups of the Makefile and .gitignore. Signed-off-by: Masahiro Yamada Signed-off-by: Russell King (Oracle) --- arch/arm/boot/compressed/.gitignore | 5 ----- arch/arm/boot/compressed/Makefile | 33 +++------------------------- arch/arm/boot/compressed/ashldi3.S | 3 +++ arch/arm/boot/compressed/bswapsdi2.S | 3 +++ arch/arm/boot/compressed/font.c | 2 ++ arch/arm/boot/compressed/hyp-stub.S | 2 ++ arch/arm/boot/compressed/lib1funcs.S | 3 +++ scripts/remove-stale-files | 2 +- 8 files changed, 17 insertions(+), 36 deletions(-) create mode 100644 arch/arm/boot/compressed/ashldi3.S create mode 100644 arch/arm/boot/compressed/bswapsdi2.S create mode 100644 arch/arm/boot/compressed/font.c create mode 100644 arch/arm/boot/compressed/hyp-stub.S create mode 100644 arch/arm/boot/compressed/lib1funcs.S diff --git a/arch/arm/boot/compressed/.gitignore b/arch/arm/boot/compressed/.gitignore index 60606b0f378d..d32f41778437 100644 --- a/arch/arm/boot/compressed/.gitignore +++ b/arch/arm/boot/compressed/.gitignore @@ -1,9 +1,4 @@ # SPDX-License-Identifier: GPL-2.0-only -ashldi3.S -bswapsdi2.S -font.c -lib1funcs.S -hyp-stub.S piggy_data vmlinux vmlinux.lds diff --git a/arch/arm/boot/compressed/Makefile b/arch/arm/boot/compressed/Makefile index 91265e7ff672..74d2f1401acb 100644 --- a/arch/arm/boot/compressed/Makefile +++ b/arch/arm/boot/compressed/Makefile @@ -13,7 +13,6 @@ ifeq ($(CONFIG_DEBUG_UNCOMPRESS),y) OBJS += debug.o AFLAGS_head.o += -DDEBUG endif -FONTC = $(srctree)/lib/fonts/font_acorn_8x8.c # string library code (-Os is enforced to keep it much smaller) OBJS += string.o @@ -99,11 +98,8 @@ $(foreach o, $(libfdt_objs) atags_to_fdt.o fdt_check_mem_start.o, \ $(eval CFLAGS_$(o) := -I $(srctree)/scripts/dtc/libfdt -fno-stack-protector)) targets := vmlinux vmlinux.lds piggy_data piggy.o \ - lib1funcs.o ashldi3.o bswapsdi2.o \ head.o $(OBJS) -clean-files += lib1funcs.S ashldi3.S bswapsdi2.S hyp-stub.S - KBUILD_CFLAGS += -DDISABLE_BRANCH_PROFILING ccflags-y := -fpic $(call cc-option,-mno-single-pic-base,) -fno-builtin \ @@ -134,23 +130,7 @@ endif # Next argument is a linker script LDFLAGS_vmlinux += -T -# For __aeabi_uidivmod -lib1funcs = $(obj)/lib1funcs.o - -$(obj)/lib1funcs.S: $(srctree)/arch/$(SRCARCH)/lib/lib1funcs.S - $(call cmd,shipped) - -# For __aeabi_llsl -ashldi3 = $(obj)/ashldi3.o - -$(obj)/ashldi3.S: $(srctree)/arch/$(SRCARCH)/lib/ashldi3.S - $(call cmd,shipped) - -# For __bswapsi2, __bswapdi2 -bswapsdi2 = $(obj)/bswapsdi2.o - -$(obj)/bswapsdi2.S: $(srctree)/arch/$(SRCARCH)/lib/bswapsdi2.S - $(call cmd,shipped) +OBJS += lib1funcs.o ashldi3.o bswapsdi2.o # We need to prevent any GOTOFF relocs being used with references # to symbols in the .bss section since we cannot relocate them @@ -175,8 +155,8 @@ fi efi-obj-$(CONFIG_EFI_STUB) := $(objtree)/drivers/firmware/efi/libstub/lib.a $(obj)/vmlinux: $(obj)/vmlinux.lds $(obj)/$(HEAD) $(obj)/piggy.o \ - $(addprefix $(obj)/, $(OBJS)) $(lib1funcs) $(ashldi3) \ - $(bswapsdi2) $(efi-obj-y) FORCE + $(addprefix $(obj)/, $(OBJS)) \ + $(efi-obj-y) FORCE @$(check_for_multiple_zreladdr) $(call if_changed,ld) @$(check_for_bad_syms) @@ -187,11 +167,4 @@ $(obj)/piggy_data: $(obj)/../Image FORCE $(obj)/piggy.o: $(obj)/piggy_data CFLAGS_font.o := -Dstatic= - -$(obj)/font.c: $(FONTC) - $(call cmd,shipped) - AFLAGS_hyp-stub.o := -Wa,-march=armv7-a - -$(obj)/hyp-stub.S: $(srctree)/arch/$(SRCARCH)/kernel/hyp-stub.S - $(call cmd,shipped) diff --git a/arch/arm/boot/compressed/ashldi3.S b/arch/arm/boot/compressed/ashldi3.S new file mode 100644 index 000000000000..216f82eda609 --- /dev/null +++ b/arch/arm/boot/compressed/ashldi3.S @@ -0,0 +1,3 @@ +/* SPDX-License-Identifier: GPL-2.0-only */ +/* For __aeabi_llsl */ +#include "../../lib/ashldi3.S" diff --git a/arch/arm/boot/compressed/bswapsdi2.S b/arch/arm/boot/compressed/bswapsdi2.S new file mode 100644 index 000000000000..b2156b378c7b --- /dev/null +++ b/arch/arm/boot/compressed/bswapsdi2.S @@ -0,0 +1,3 @@ +/* SPDX-License-Identifier: GPL-2.0-only */ +/* For __bswapsi2, __bswapdi2 */ +#include "../../lib/bswapsdi2.S" diff --git a/arch/arm/boot/compressed/font.c b/arch/arm/boot/compressed/font.c new file mode 100644 index 000000000000..46a677649db4 --- /dev/null +++ b/arch/arm/boot/compressed/font.c @@ -0,0 +1,2 @@ +// SPDX-License-Identifier: GPL-2.0-only +#include "../../../../lib/fonts/font_acorn_8x8.c" diff --git a/arch/arm/boot/compressed/hyp-stub.S b/arch/arm/boot/compressed/hyp-stub.S new file mode 100644 index 000000000000..a703eaa86f10 --- /dev/null +++ b/arch/arm/boot/compressed/hyp-stub.S @@ -0,0 +1,2 @@ +/* SPDX-License-Identifier: GPL-2.0-only */ +#include "../../kernel/hyp-stub.S" diff --git a/arch/arm/boot/compressed/lib1funcs.S b/arch/arm/boot/compressed/lib1funcs.S new file mode 100644 index 000000000000..815dec73ba4d --- /dev/null +++ b/arch/arm/boot/compressed/lib1funcs.S @@ -0,0 +1,3 @@ +/* SPDX-License-Identifier: GPL-2.0-only */ +/* For __aeabi_uidivmod */ +#include "../../lib/lib1funcs.S" diff --git a/scripts/remove-stale-files b/scripts/remove-stale-files index 0114c41e6938..f0d53227fe7b 100755 --- a/scripts/remove-stale-files +++ b/scripts/remove-stale-files @@ -24,7 +24,7 @@ set -e # with O=, make sure to remove the stale files in the output tree. Otherwise, # the build system wrongly compiles the stale ones. if [ -n "${building_out_of_srctree}" ]; then - for f in fdt_rw.c fdt_ro.c fdt_wip.c fdt.c + for f in fdt_rw.c fdt_ro.c fdt_wip.c fdt.c ashldi3.S bswapsdi2.S font.c lib1funcs.S hyp-stub.S do rm -f arch/arm/boot/compressed/${f} done From 4a2f57ac7dada84224d71fe895580990b9062d68 Mon Sep 17 00:00:00 2001 From: Ard Biesheuvel Date: Mon, 15 Nov 2021 08:57:12 +0100 Subject: [PATCH 02/12] ARM: 9158/1: leave it to core code to manage thread_info::cpu Since commit bcf9033e5449 ("sched: move CPU field back into thread_info if THREAD_INFO_IN_TASK=y"), the CPU field in thread_info went back to being managed by the core code, so we no longer have to keep it in sync in arch code. While at it, mark THREAD_INFO_IN_TASK as done for ARM in the documentation. Reviewed-by: Linus Walleij Signed-off-by: Ard Biesheuvel Signed-off-by: Russell King (Oracle) --- .../core/thread-info-in-task/arch-support.txt | 2 +- arch/arm/include/asm/switch_to.h | 14 -------------- arch/arm/kernel/smp.c | 3 --- 3 files changed, 1 insertion(+), 18 deletions(-) diff --git a/Documentation/features/core/thread-info-in-task/arch-support.txt b/Documentation/features/core/thread-info-in-task/arch-support.txt index 3361e86b0958..bc74d8beea72 100644 --- a/Documentation/features/core/thread-info-in-task/arch-support.txt +++ b/Documentation/features/core/thread-info-in-task/arch-support.txt @@ -8,7 +8,7 @@ ----------------------- | alpha: | TODO | | arc: | TODO | - | arm: | TODO | + | arm: | ok | | arm64: | ok | | csky: | TODO | | h8300: | TODO | diff --git a/arch/arm/include/asm/switch_to.h b/arch/arm/include/asm/switch_to.h index b55c7b2755e4..61e4a3c4ca6e 100644 --- a/arch/arm/include/asm/switch_to.h +++ b/arch/arm/include/asm/switch_to.h @@ -23,23 +23,9 @@ */ extern struct task_struct *__switch_to(struct task_struct *, struct thread_info *, struct thread_info *); -static inline void set_ti_cpu(struct task_struct *p) -{ -#ifdef CONFIG_THREAD_INFO_IN_TASK - /* - * The core code no longer maintains the thread_info::cpu field once - * CONFIG_THREAD_INFO_IN_TASK is in effect, but we rely on it for - * raw_smp_processor_id(), which cannot access struct task_struct* - * directly for reasons of circular #inclusion hell. - */ - task_thread_info(p)->cpu = task_cpu(p); -#endif -} - #define switch_to(prev,next,last) \ do { \ __complete_pending_tlbi(); \ - set_ti_cpu(next); \ if (IS_ENABLED(CONFIG_CURRENT_POINTER_IN_TPIDRURO)) \ __this_cpu_write(__entry_task, next); \ last = __switch_to(prev,task_thread_info(prev), task_thread_info(next)); \ diff --git a/arch/arm/kernel/smp.c b/arch/arm/kernel/smp.c index cde5b6d8bac5..97ee6b1567e9 100644 --- a/arch/arm/kernel/smp.c +++ b/arch/arm/kernel/smp.c @@ -154,9 +154,6 @@ int __cpu_up(unsigned int cpu, struct task_struct *idle) secondary_data.swapper_pg_dir = get_arch_pgd(swapper_pg_dir); #endif secondary_data.task = idle; - if (IS_ENABLED(CONFIG_THREAD_INFO_IN_TASK)) - task_thread_info(idle)->cpu = cpu; - sync_cache_w(&secondary_data); /* From a92882a4d270fbcc021ee6848de5e48b7f0d27f3 Mon Sep 17 00:00:00 2001 From: Andre Przywara Date: Mon, 22 Nov 2021 16:28:43 +0100 Subject: [PATCH 03/12] ARM: 9159/1: decompressor: Avoid UNPREDICTABLE NOP encoding In the decompressor's head.S we need to start with an instruction that is some kind of NOP, but also mimics as the PE/COFF header, when the kernel is linked as an UEFI application. The clever solution here is "tstne r0, #0x4d000", which in the worst case just clobbers the condition flags, and bears the magic "MZ" signature in the lowest 16 bits. However the encoding used (0x13105a4d) is actually not valid, since bits [15:12] are supposed to be 0 (written as "(0)" in the ARM ARM). Violating this is UNPREDICTABLE, and *can* trigger an UNDEFINED exception. Common Cortex cores seem to ignore those bits, but QEMU chooses to trap, so the code goes fishing because of a missing exception handler at this point. We are just saved by the fact that commonly (with -kernel or when running from U-Boot) the "Z" bit is set, so the instruction is never executed. See [0] for more details. To make things more robust and avoid UNPREDICTABLE behaviour in the kernel code, lets replace this with a "two-instruction NOP": The first instruction is an exclusive OR, the effect of which the second instruction reverts. This does not leave any trace, neither in a register nor in the condition flags. Also it's a perfectly valid encoding. Kudos to Peter Maydell for coming up with this gem. [0] https://lore.kernel.org/qemu-devel/YTPIdbUCmwagL5%2FD@os.inf.tu-dresden.de/T/ Link: https://lore.kernel.org/linux-arm-kernel/20210908162617.104962-1-andre.przywara@arm.com/T/ Fixes: 81a0bc39ea19 ("ARM: add UEFI stub support") Signed-off-by: Andre Przywara Reported-by: Adam Lackorzynski Suggested-by: Peter Maydell Reviewed-by: Ard Biesheuvel Reviewed-by: Linus Walleij Signed-off-by: Russell King (Oracle) --- arch/arm/boot/compressed/efi-header.S | 22 ++++++++++++++-------- arch/arm/boot/compressed/head.S | 3 ++- 2 files changed, 16 insertions(+), 9 deletions(-) diff --git a/arch/arm/boot/compressed/efi-header.S b/arch/arm/boot/compressed/efi-header.S index c0e7a745103e..230030c13085 100644 --- a/arch/arm/boot/compressed/efi-header.S +++ b/arch/arm/boot/compressed/efi-header.S @@ -9,16 +9,22 @@ #include .macro __nop -#ifdef CONFIG_EFI_STUB - @ This is almost but not quite a NOP, since it does clobber the - @ condition flags. But it is the best we can do for EFI, since - @ PE/COFF expects the magic string "MZ" at offset 0, while the - @ ARM/Linux boot protocol expects an executable instruction - @ there. - .inst MZ_MAGIC | (0x1310 << 16) @ tstne r0, #0x4d000 -#else AR_CLASS( mov r0, r0 ) M_CLASS( nop.w ) + .endm + + .macro __initial_nops +#ifdef CONFIG_EFI_STUB + @ This is a two-instruction NOP, which happens to bear the + @ PE/COFF signature "MZ" in the first two bytes, so the kernel + @ is accepted as an EFI binary. Booting via the UEFI stub + @ will not execute those instructions, but the ARM/Linux + @ boot protocol does, so we need some NOPs here. + .inst MZ_MAGIC | (0xe225 << 16) @ eor r5, r5, 0x4d000 + eor r5, r5, 0x4d000 @ undo previous insn +#else + __nop + __nop #endif .endm diff --git a/arch/arm/boot/compressed/head.S b/arch/arm/boot/compressed/head.S index b1cb1972361b..bf79f2f78d23 100644 --- a/arch/arm/boot/compressed/head.S +++ b/arch/arm/boot/compressed/head.S @@ -203,7 +203,8 @@ start: * were patching the initial instructions of the kernel, i.e * had started to exploit this "patch area". */ - .rept 7 + __initial_nops + .rept 5 __nop .endr #ifndef CONFIG_THUMB2_KERNEL From d0eae8287cf3dff6670e7e9910159942bda45a20 Mon Sep 17 00:00:00 2001 From: Wang Kefeng Date: Fri, 3 Dec 2021 10:21:42 +0100 Subject: [PATCH 04/12] ARM: 9161/1: mm: mark private VM_FAULT_X defines as vm_fault_t This fixes several sparse warnings for fault.c: arch/arm/mm/fault.c:210:24: sparse: expected restricted vm_fault_t arch/arm/mm/fault.c:210:24: sparse: got int ... arch/arm/mm/fault.c:345:24: sparse: sparse: restricted vm_fault_t degrades to integer Reported-by: kernel test robot Fixes: caed89dab0ca ("ARM: 9128/1: mm: Refactor the __do_page_fault()") Signed-off-by: Kefeng Wang Signed-off-by: Russell King (Oracle) --- arch/arm/mm/fault.c | 4 ++-- 1 file changed, 2 insertions(+), 2 deletions(-) diff --git a/arch/arm/mm/fault.c b/arch/arm/mm/fault.c index bc8779d54a64..013921a5909b 100644 --- a/arch/arm/mm/fault.c +++ b/arch/arm/mm/fault.c @@ -191,8 +191,8 @@ void do_bad_area(unsigned long addr, unsigned int fsr, struct pt_regs *regs) } #ifdef CONFIG_MMU -#define VM_FAULT_BADMAP 0x010000 -#define VM_FAULT_BADACCESS 0x020000 +#define VM_FAULT_BADMAP ((__force vm_fault_t)0x010000) +#define VM_FAULT_BADACCESS ((__force vm_fault_t)0x020000) static inline bool is_permission_fault(unsigned int fsr) { From 33c6a549641db662621b4bf6993df1589669aaac Mon Sep 17 00:00:00 2001 From: Wang Kefeng Date: Fri, 3 Dec 2021 10:25:20 +0100 Subject: [PATCH 05/12] ARM: 9162/1: amba: Kill sysfs attribute file of irq As Rob said[1], there doesn't seem to be any users about the sysfs attribute file of irq[0] and irq[1]. And we don't need to include as NO_IRQ has gone. Let's kill both of them. [1] https://lkml.org/lkml/2021/8/25/461 Acked-by: Rob Herring Signed-off-by: Kefeng Wang Signed-off-by: Russell King (Oracle) --- drivers/amba/bus.c | 19 ++----------------- 1 file changed, 2 insertions(+), 17 deletions(-) diff --git a/drivers/amba/bus.c b/drivers/amba/bus.c index 720aa6cdd402..16d3c009505b 100644 --- a/drivers/amba/bus.c +++ b/drivers/amba/bus.c @@ -21,8 +21,6 @@ #include #include -#include - #define to_amba_driver(d) container_of(d, struct amba_driver, drv) /* called on periphid match and class 0x9 coresight device. */ @@ -136,8 +134,6 @@ static ssize_t name##_show(struct device *_dev, \ static DEVICE_ATTR_RO(name) amba_attr_func(id, "%08x\n", dev->periphid); -amba_attr_func(irq0, "%u\n", dev->irq[0]); -amba_attr_func(irq1, "%u\n", dev->irq[1]); amba_attr_func(resource, "\t%016llx\t%016llx\t%016lx\n", (unsigned long long)dev->res.start, (unsigned long long)dev->res.end, dev->res.flags); @@ -488,20 +484,9 @@ static int amba_device_try_add(struct amba_device *dev, struct resource *parent) skip_probe: ret = device_add(&dev->dev); - if (ret) - goto err_release; - - if (dev->irq[0]) - ret = device_create_file(&dev->dev, &dev_attr_irq0); - if (ret == 0 && dev->irq[1]) - ret = device_create_file(&dev->dev, &dev_attr_irq1); - if (ret == 0) - return ret; - - device_unregister(&dev->dev); - err_release: - release_resource(&dev->res); + if (ret) + release_resource(&dev->res); err_out: return ret; From dcc0a8f6b69a42cdf557e1e554478204c139082d Mon Sep 17 00:00:00 2001 From: Wang Kefeng Date: Fri, 3 Dec 2021 10:25:21 +0100 Subject: [PATCH 06/12] ARM: 9163/1: amba: Move of_amba_device_decode_irq() into amba_probe() Similar to other resources the AMBA bus "gets" for the device, move irq obtain from amba_device_add() to amba_probe(). Signed-off-by: Kefeng Wang Signed-off-by: Russell King (Oracle) --- drivers/amba/bus.c | 52 +++++++++++++++++++++++----------------------- 1 file changed, 26 insertions(+), 26 deletions(-) diff --git a/drivers/amba/bus.c b/drivers/amba/bus.c index 16d3c009505b..e1a5eca3ae3c 100644 --- a/drivers/amba/bus.c +++ b/drivers/amba/bus.c @@ -171,6 +171,28 @@ static int amba_uevent(struct device *dev, struct kobj_uevent_env *env) return retval; } +static int of_amba_device_decode_irq(struct amba_device *dev) +{ + struct device_node *node = dev->dev.of_node; + int i, irq = 0; + + if (IS_ENABLED(CONFIG_OF_IRQ) && node) { + /* Decode the IRQs and address ranges */ + for (i = 0; i < AMBA_NR_IRQS; i++) { + irq = of_irq_get(node, i); + if (irq < 0) { + if (irq == -EPROBE_DEFER) + return irq; + irq = 0; + } + + dev->irq[i] = irq; + } + } + + return 0; +} + /* * These are the device model conversion veneers; they convert the * device model structures to our more specific structures. @@ -183,6 +205,10 @@ static int amba_probe(struct device *dev) int ret; do { + ret = of_amba_device_decode_irq(pcdev); + if (ret) + break; + ret = of_clk_set_defaults(dev->of_node, false); if (ret < 0) break; @@ -368,38 +394,12 @@ static void amba_device_release(struct device *dev) kfree(d); } -static int of_amba_device_decode_irq(struct amba_device *dev) -{ - struct device_node *node = dev->dev.of_node; - int i, irq = 0; - - if (IS_ENABLED(CONFIG_OF_IRQ) && node) { - /* Decode the IRQs and address ranges */ - for (i = 0; i < AMBA_NR_IRQS; i++) { - irq = of_irq_get(node, i); - if (irq < 0) { - if (irq == -EPROBE_DEFER) - return irq; - irq = 0; - } - - dev->irq[i] = irq; - } - } - - return 0; -} - static int amba_device_try_add(struct amba_device *dev, struct resource *parent) { u32 size; void __iomem *tmp; int i, ret; - ret = of_amba_device_decode_irq(dev); - if (ret) - goto err_out; - ret = request_resource(parent, &dev->res); if (ret) goto err_out; From 0ba8695e3dfbbc78ed716805678119121d33a730 Mon Sep 17 00:00:00 2001 From: Wang Kefeng Date: Fri, 3 Dec 2021 10:26:31 +0100 Subject: [PATCH 07/12] ARM: 9164/1: mm: Provide set_memory_valid() This function validates and invalidates PTE entries, it will be used in the later patch. Acked-by: Marco Elver Signed-off-by: Kefeng Wang Signed-off-by: Russell King (Oracle) --- arch/arm/include/asm/set_memory.h | 1 + arch/arm/mm/pageattr.c | 42 +++++++++++++++++++++++-------- 2 files changed, 33 insertions(+), 10 deletions(-) diff --git a/arch/arm/include/asm/set_memory.h b/arch/arm/include/asm/set_memory.h index ec17fc0fda7a..0211b9c5b14d 100644 --- a/arch/arm/include/asm/set_memory.h +++ b/arch/arm/include/asm/set_memory.h @@ -11,6 +11,7 @@ int set_memory_ro(unsigned long addr, int numpages); int set_memory_rw(unsigned long addr, int numpages); int set_memory_x(unsigned long addr, int numpages); int set_memory_nx(unsigned long addr, int numpages); +int set_memory_valid(unsigned long addr, int numpages, int enable); #else static inline int set_memory_ro(unsigned long addr, int numpages) { return 0; } static inline int set_memory_rw(unsigned long addr, int numpages) { return 0; } diff --git a/arch/arm/mm/pageattr.c b/arch/arm/mm/pageattr.c index 9790ae3a8c68..c3c34fe714b0 100644 --- a/arch/arm/mm/pageattr.c +++ b/arch/arm/mm/pageattr.c @@ -32,14 +32,31 @@ static bool in_range(unsigned long start, unsigned long size, size <= range_end - start; } +/* + * This function assumes that the range is mapped with PAGE_SIZE pages. + */ +static int __change_memory_common(unsigned long start, unsigned long size, + pgprot_t set_mask, pgprot_t clear_mask) +{ + struct page_change_data data; + int ret; + + data.set_mask = set_mask; + data.clear_mask = clear_mask; + + ret = apply_to_page_range(&init_mm, start, size, change_page_range, + &data); + + flush_tlb_kernel_range(start, start + size); + return ret; +} + static int change_memory_common(unsigned long addr, int numpages, pgprot_t set_mask, pgprot_t clear_mask) { unsigned long start = addr & PAGE_MASK; unsigned long end = PAGE_ALIGN(addr) + numpages * PAGE_SIZE; unsigned long size = end - start; - int ret; - struct page_change_data data; WARN_ON_ONCE(start != addr); @@ -50,14 +67,7 @@ static int change_memory_common(unsigned long addr, int numpages, !in_range(start, size, VMALLOC_START, VMALLOC_END)) return -EINVAL; - data.set_mask = set_mask; - data.clear_mask = clear_mask; - - ret = apply_to_page_range(&init_mm, start, size, change_page_range, - &data); - - flush_tlb_kernel_range(start, end); - return ret; + return __change_memory_common(start, size, set_mask, clear_mask); } int set_memory_ro(unsigned long addr, int numpages) @@ -87,3 +97,15 @@ int set_memory_x(unsigned long addr, int numpages) __pgprot(0), __pgprot(L_PTE_XN)); } + +int set_memory_valid(unsigned long addr, int numpages, int enable) +{ + if (enable) + return __change_memory_common(addr, PAGE_SIZE * numpages, + __pgprot(L_PTE_VALID), + __pgprot(0)); + else + return __change_memory_common(addr, PAGE_SIZE * numpages, + __pgprot(0), + __pgprot(L_PTE_VALID)); +} From 3c341b217414d1d63718438f2b2fa588cf2b73fc Mon Sep 17 00:00:00 2001 From: Wang Kefeng Date: Fri, 3 Dec 2021 10:26:32 +0100 Subject: [PATCH 08/12] ARM: 9165/1: mm: Provide is_write_fault() The function will check whether the fault is caused by a write access, it will be called in die_kernel_fault() too in next patch, so put it before the function of die_kernel_fault(). Acked-by: Marco Elver Signed-off-by: Kefeng Wang Signed-off-by: Russell King (Oracle) --- arch/arm/mm/fault.c | 7 ++++++- 1 file changed, 6 insertions(+), 1 deletion(-) diff --git a/arch/arm/mm/fault.c b/arch/arm/mm/fault.c index 013921a5909b..1d41e8fad4f3 100644 --- a/arch/arm/mm/fault.c +++ b/arch/arm/mm/fault.c @@ -99,6 +99,11 @@ void show_pte(const char *lvl, struct mm_struct *mm, unsigned long addr) { } #endif /* CONFIG_MMU */ +static inline bool is_write_fault(unsigned int fsr) +{ + return (fsr & FSR_WRITE) && !(fsr & FSR_CM); +} + static void die_kernel_fault(const char *msg, struct mm_struct *mm, unsigned long addr, unsigned int fsr, struct pt_regs *regs) @@ -261,7 +266,7 @@ do_page_fault(unsigned long addr, unsigned int fsr, struct pt_regs *regs) if (user_mode(regs)) flags |= FAULT_FLAG_USER; - if ((fsr & FSR_WRITE) && !(fsr & FSR_CM)) { + if (is_write_fault(fsr)) { flags |= FAULT_FLAG_WRITE; vm_flags = VM_WRITE; } From 75969686ec0df23157afe24dc818d7bddb087d78 Mon Sep 17 00:00:00 2001 From: Wang Kefeng Date: Fri, 3 Dec 2021 10:26:33 +0100 Subject: [PATCH 09/12] ARM: 9166/1: Support KFENCE for ARM Add architecture specific implementation details for KFENCE and enable KFENCE on ARM. In particular, this implements the required interface in . KFENCE requires that attributes for pages from its memory pool can individually be set. Therefore, force the kfence pool to be mapped at page granularity. Testing this patch using the testcases in kfence_test.c and all passed with or without ARM_LPAE. Acked-by: Marco Elver Signed-off-by: Kefeng Wang Signed-off-by: Russell King (Oracle) --- arch/arm/Kconfig | 1 + arch/arm/include/asm/kfence.h | 53 +++++++++++++++++++++++++++++++++++ arch/arm/mm/fault.c | 9 ++++-- 3 files changed, 61 insertions(+), 2 deletions(-) create mode 100644 arch/arm/include/asm/kfence.h diff --git a/arch/arm/Kconfig b/arch/arm/Kconfig index f0f9e8bec83a..321b0a1c2820 100644 --- a/arch/arm/Kconfig +++ b/arch/arm/Kconfig @@ -69,6 +69,7 @@ config ARM select HAVE_ARCH_AUDITSYSCALL if AEABI && !OABI_COMPAT select HAVE_ARCH_BITREVERSE if (CPU_32v7M || CPU_32v7) && !CPU_32v6 select HAVE_ARCH_JUMP_LABEL if !XIP_KERNEL && !CPU_ENDIAN_BE32 && MMU + select HAVE_ARCH_KFENCE if MMU && !XIP_KERNEL select HAVE_ARCH_KGDB if !CPU_ENDIAN_BE32 && MMU select HAVE_ARCH_KASAN if MMU && !XIP_KERNEL select HAVE_ARCH_MMAP_RND_BITS if MMU diff --git a/arch/arm/include/asm/kfence.h b/arch/arm/include/asm/kfence.h new file mode 100644 index 000000000000..7980d0f2271f --- /dev/null +++ b/arch/arm/include/asm/kfence.h @@ -0,0 +1,53 @@ +/* SPDX-License-Identifier: GPL-2.0 */ + +#ifndef __ASM_ARM_KFENCE_H +#define __ASM_ARM_KFENCE_H + +#include + +#include +#include + +static inline int split_pmd_page(pmd_t *pmd, unsigned long addr) +{ + int i; + unsigned long pfn = PFN_DOWN(__pa(addr)); + pte_t *pte = pte_alloc_one_kernel(&init_mm); + + if (!pte) + return -ENOMEM; + + for (i = 0; i < PTRS_PER_PTE; i++) + set_pte_ext(pte + i, pfn_pte(pfn + i, PAGE_KERNEL), 0); + pmd_populate_kernel(&init_mm, pmd, pte); + + flush_tlb_kernel_range(addr, addr + PMD_SIZE); + return 0; +} + +static inline bool arch_kfence_init_pool(void) +{ + unsigned long addr; + pmd_t *pmd; + + for (addr = (unsigned long)__kfence_pool; is_kfence_address((void *)addr); + addr += PAGE_SIZE) { + pmd = pmd_off_k(addr); + + if (pmd_leaf(*pmd)) { + if (split_pmd_page(pmd, addr & PMD_MASK)) + return false; + } + } + + return true; +} + +static inline bool kfence_protect_page(unsigned long addr, bool protect) +{ + set_memory_valid(addr, 1, !protect); + + return true; +} + +#endif /* __ASM_ARM_KFENCE_H */ diff --git a/arch/arm/mm/fault.c b/arch/arm/mm/fault.c index 1d41e8fad4f3..a1cebe363ed5 100644 --- a/arch/arm/mm/fault.c +++ b/arch/arm/mm/fault.c @@ -17,6 +17,7 @@ #include #include #include +#include #include #include @@ -136,10 +137,14 @@ __do_kernel_fault(struct mm_struct *mm, unsigned long addr, unsigned int fsr, /* * No handler, we'll have to terminate things with extreme prejudice. */ - if (addr < PAGE_SIZE) + if (addr < PAGE_SIZE) { msg = "NULL pointer dereference"; - else + } else { + if (kfence_handle_page_fault(addr, is_write_fault(fsr), regs)) + return; + msg = "paging request"; + } die_kernel_fault(msg, mm, addr, fsr, regs); } From 2965d4290f6052a9e7b47bad6ff648b867293488 Mon Sep 17 00:00:00 2001 From: Vladimir Murzin Date: Fri, 10 Dec 2021 14:49:43 +0100 Subject: [PATCH 10/12] ARM: 9167/1: Add support for Cortex-M33 processor Cortex-M33 is the first feature rich implementation of the Armv8-M architecture (still compatible with v7M) Signed-off-by: Vladimir Murzin Signed-off-by: Russell King (Oracle) --- arch/arm/mm/proc-v7m.S | 10 ++++++++++ 1 file changed, 10 insertions(+) diff --git a/arch/arm/mm/proc-v7m.S b/arch/arm/mm/proc-v7m.S index 84459c1d31b8..fc1263710d0f 100644 --- a/arch/arm/mm/proc-v7m.S +++ b/arch/arm/mm/proc-v7m.S @@ -193,6 +193,16 @@ ENDPROC(__v7m_setup) .long \cache_fns .endm + /* + * Match ARM Cortex-M33 processor. + */ + .type __v7m_cm33_proc_info, #object +__v7m_cm33_proc_info: + .long 0x410fd210 /* ARM Cortex-M33 0xD21 */ + .long 0xff0ffff0 /* Mask off revision, patch release */ + __v7m_proc __v7m_cm33_proc_info, __v7m_setup, hwcaps = HWCAP_EDSP + .size __v7m_cm33_proc_info, . - __v7m_cm33_proc_info + /* * Match ARM Cortex-M7 processor. */ From 3d14751f341e4778f967f2799eceef23a2dba8a0 Mon Sep 17 00:00:00 2001 From: Tigran Tadevosyan Date: Fri, 10 Dec 2021 14:50:31 +0100 Subject: [PATCH 11/12] ARM: 9168/1: Add support for Cortex-M55 processor Add processor info object for ARM Cortex-M55 CPU which inherits the setup procedure, the processor and cache operation function from Cortex-M7 processor info object. Signed-off-by: Tigran Tadevosyan Signed-off-by: Vladimir Murzin Signed-off-by: Russell King (Oracle) --- arch/arm/mm/proc-v7m.S | 10 ++++++++++ 1 file changed, 10 insertions(+) diff --git a/arch/arm/mm/proc-v7m.S b/arch/arm/mm/proc-v7m.S index fc1263710d0f..335144d50134 100644 --- a/arch/arm/mm/proc-v7m.S +++ b/arch/arm/mm/proc-v7m.S @@ -193,6 +193,16 @@ ENDPROC(__v7m_setup) .long \cache_fns .endm + /* + * Match ARM Cortex-M55 processor. + */ + .type __v7m_cm55_proc_info, #object +__v7m_cm55_proc_info: + .long 0x410fd220 /* ARM Cortex-M55 0xD22 */ + .long 0xff0ffff0 /* Mask off revision, patch release */ + __v7m_proc __v7m_cm55_proc_info, __v7m_cm7_setup, hwcaps = HWCAP_EDSP, cache_fns = v7m_cache_fns, proc_fns = cm7_processor_functions + .size __v7m_cm55_proc_info, . - __v7m_cm55_proc_info + /* * Match ARM Cortex-M33 processor. */ From b0343ab330ae4d6c8d4210de5c16da704c2d4743 Mon Sep 17 00:00:00 2001 From: Russell King Date: Thu, 13 May 2021 10:59:23 +0100 Subject: [PATCH 12/12] ARM: reduce the information printed in call traces A while back, Linus complained about the numeric values printed by the ARM backtracing code. Printing these values does not make sense if one does not have access to the kernel ELF image (as is normally the case when helping a third party on a mailing list), but if one does, they can be very useful to find the code, rather than searching for the function name, and then doing hex math to work out where the backtrace entry is referring to. Provide an option to control whether this information is included, which will only be visible if EXPERT is enabled. Signed-off-by: Russell King --- arch/arm/Kconfig.debug | 11 +++++++++++ arch/arm/kernel/traps.c | 8 +++++--- 2 files changed, 16 insertions(+), 3 deletions(-) diff --git a/arch/arm/Kconfig.debug b/arch/arm/Kconfig.debug index 98436702e0c7..07055a503022 100644 --- a/arch/arm/Kconfig.debug +++ b/arch/arm/Kconfig.debug @@ -81,6 +81,17 @@ endchoice config ARM_UNWIND bool +config BACKTRACE_VERBOSE + bool "Verbose backtrace" + depends on EXPERT + help + When the kernel produces a warning or oops, the kernel prints a + trace of the call chain. This option controls whether we include + the numeric addresses or only include the symbolic information. + + In most cases, say N here, unless you are intending to debug the + kernel and have access to the kernel binary image. + config FRAME_POINTER bool diff --git a/arch/arm/kernel/traps.c b/arch/arm/kernel/traps.c index 195dff58bafc..c5e25cf7219b 100644 --- a/arch/arm/kernel/traps.c +++ b/arch/arm/kernel/traps.c @@ -67,12 +67,14 @@ void dump_backtrace_entry(unsigned long where, unsigned long from, { unsigned long end = frame + 4 + sizeof(struct pt_regs); -#ifdef CONFIG_KALLSYMS +#ifndef CONFIG_KALLSYMS + printk("%sFunction entered at [<%08lx>] from [<%08lx>]\n", + loglvl, where, from); +#elif defined CONFIG_BACKTRACE_VERBOSE printk("%s[<%08lx>] (%ps) from [<%08lx>] (%pS)\n", loglvl, where, (void *)where, from, (void *)from); #else - printk("%sFunction entered at [<%08lx>] from [<%08lx>]\n", - loglvl, where, from); + printk("%s %ps from %pS\n", loglvl, (void *)where, (void *)from); #endif if (in_entry_text(from) && end <= ALIGN(frame, THREAD_SIZE))