kernel.git/arch/sparc, branch linux-4.14.y

sparc: fix up arch_cpu_finalize_init() build breakage.

2023-08-16T16:10:53Z

In commit 39f0e159b8e8 ("sparc/cpu: Switch to arch_cpu_finalize_init()") the check for ARCH_HAS_CPU_FINALIZE_INIT was backported incorrectly to the SPARC config option, not SPARC32. This causes build problems for the sparc64 arch: sparc64-linux-ld: init/main.o: in function `start_kernel': main.c:(.init.text+0x77c): undefined reference to `arch_cpu_finalize_init' Fix this up by putting the option in the correct place. Reported-by: Guenter Roeck Link: https://lore.kernel.org/r/252c7673-53ee-4c4b-e5ef-5bb2c0416154@roeck-us.net Fixes: 39f0e159b8e8 ("sparc/cpu: Switch to arch_cpu_finalize_init()") Signed-off-by: Greg Kroah-Hartman

sparc/cpu: Switch to arch_cpu_finalize_init()

2023-08-08T17:48:24Z

commit 44ade508e3bfac45ae97864587de29eb1a881ec0 upstream check_bugs() is about to be phased out. Switch over to the new arch_cpu_finalize_init() implementation. No functional change. Signed-off-by: Thomas Gleixner Reviewed-by: Sam Ravnborg Link: https://lore.kernel.org/r/20230613224545.431995857@linutronix.de Signed-off-by: Daniel Sneddon Signed-off-by: Greg Kroah-Hartman

exit: Add and use make_task_dead.

2023-02-06T06:46:33Z

commit 0e25498f8cd43c1b5aa327f373dd094e9a006da7 upstream. There are two big uses of do_exit. The first is it's design use to be the guts of the exit(2) system call. The second use is to terminate a task after something catastrophic has happened like a NULL pointer in kernel code. Add a function make_task_dead that is initialy exactly the same as do_exit to cover the cases where do_exit is called to handle catastrophic failure. In time this can probably be reduced to just a light wrapper around do_task_dead. For now keep it exactly the same so that there will be no behavioral differences introducing this new concept. Replace all of the uses of do_exit that use it for catastraphic task cleanup with make_task_dead to make it clear what the code is doing. As part of this rename rewind_stack_do_exit rewind_stack_and_make_dead. Signed-off-by: "Eric W. Biederman" Signed-off-by: Eric Biggers Signed-off-by: Greg Kroah-Hartman

sparc: use fallback for random_get_entropy() instead of zero

2022-06-25T09:46:39Z

commit ac9756c79797bb98972736b13cfb239fd2cffb79 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. This is accomplished by just including the asm-generic code like on other architectures, which means we can get rid of the empty stub function here. Cc: Thomas Gleixner Cc: Arnd Bergmann Cc: David S. Miller Signed-off-by: Jason A. Donenfeld Signed-off-by: Greg Kroah-Hartman

mips,s390,sh,sparc: gup: Work around the "COW can break either way" issue

2022-01-27T08:01:01Z

In Linux 4.14 and 4.19 these architectures still have their own implementations of get_user_pages_fast(). These also need to force the write flag on when taking the fast path. Fixes: 407faed92b4a ("gup: document and work around "COW can break either way" issue") Fixes: 5e24029791e8 ("gup: document and work around "COW can break either way" issue") Signed-off-by: Ben Hutchings

sparc64: fix pci_iounmap() when CONFIG_PCI is not set

2021-10-09T12:09:46Z

[ Upstream commit d8b1e10a2b8efaf71d151aa756052fbf2f3b6d57 ] Guenter reported [1] that the pci_iounmap() changes remain problematic, with sparc64 allnoconfig and tinyconfig still not building due to the header file changes and confusion with the arch-specific pci_iounmap() implementation. I'm pretty convinced that sparc should just use GENERIC_IOMAP instead of doing its own thing, since it turns out that the sparc64 version of pci_iounmap() is somewhat buggy (see [2]). But in the meantime, this just fixes the build by avoiding the trivial re-definition of the empty case. Link: https://lore.kernel.org/lkml/20210920134424.GA346531@roeck-us.net/ [1] Link: https://lore.kernel.org/lkml/CAHk-=wgheheFx9myQyy5osh79BAazvmvYURAtub2gQtMvLrhqQ@mail.gmail.com/ [2] Reported-by: Guenter Roeck Cc: David Miller Signed-off-by: Linus Torvalds Signed-off-by: Sasha Levin

sparc: avoid stringop-overread errors

2021-10-06T13:05:07Z

[ Upstream commit fc7c028dcdbfe981bca75d2a7b95f363eb691ef3 ] The sparc mdesc code does pointer games with 'struct mdesc_hdr', but didn't describe to the compiler how that header is then followed by the data that the header describes. As a result, gcc is now unhappy since it does stricter pointer range tracking, and doesn't understand about how these things work. This results in various errors like: arch/sparc/kernel/mdesc.c: In function ‘mdesc_node_by_name’: arch/sparc/kernel/mdesc.c:647:22: error: ‘strcmp’ reading 1 or more bytes from a region of size 0 [-Werror=stringop-overread] 647 | if (!strcmp(names + ep[ret].name_offset, name)) | ^~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~ which are easily avoided by just describing 'struct mdesc_hdr' better, and making the node_block() helper function look into that unsized data[] that follows the header. This makes the sparc64 build happy again at least for my cross-compiler version (gcc version 11.2.1). Link: https://lore.kernel.org/lkml/CAHk-=wi4NW3NC0xWykkw=6LnjQD6D_rtRtxY9g8gQAJXtQMi8A@mail.gmail.com/ Cc: Guenter Roeck Cc: David S. Miller Signed-off-by: Linus Torvalds Signed-off-by: Sasha Levin

sparc64: Fix opcode filtering in handling of no fault loads

2021-03-30T12:40:09Z

[ Upstream commit e5e8b80d352ec999d2bba3ea584f541c83f4ca3f ] is_no_fault_exception() has two bugs which were discovered via random opcode testing with stress-ng. Both are caused by improper filtering of opcodes. The first bug can be triggered by a floating point store with a no-fault ASI, for instance "sta %f0, [%g0] #ASI_PNF", opcode C1A01040. The code first tests op3[5] (0x1000000), which denotes a floating point instruction, and then tests op3[2] (0x200000), which denotes a store instruction. But these bits are not mutually exclusive, and the above mentioned opcode has both bits set. The intent is to filter out stores, so the test for stores must be done first in order to have any effect. The second bug can be triggered by a floating point load with one of the invalid ASI values 0x8e or 0x8f, which pass this check in is_no_fault_exception(): if ((asi & 0xf2) == ASI_PNF) An example instruction is "ldqa [%l7 + %o7] #ASI 0x8f, %f38", opcode CF95D1EF. Asi values greater than 0x8b (ASI_SNFL) are fatal in handle_ldf_stq(), and is_no_fault_exception() must not allow these invalid asi values to make it that far. In both of these cases, handle_ldf_stq() reacts by calling sun4v_data_access_exception() or spitfire_data_access_exception(), which call is_no_fault_exception() and results in an infinite recursion. Signed-off-by: Rob Gardner Tested-by: Anatoly Pugachev Signed-off-by: David S. Miller Signed-off-by: Sasha Levin

sparc32: fix a user-triggerable oops in clear_user()

2021-03-03T17:22:55Z

commit 7780918b36489f0b2f9a3749d7be00c2ceaec513 upstream. Back in 2.1.29 the clear_user() guts (__bzero()) had been merged with memset(). Unfortunately, while all exception handlers had been copied, one of the exception table entries got lost. As the result, clear_user() starting at 128*n bytes before the end of page and spanning between 8 and 127 bytes into the next page would oops when the second page is unmapped. It's trivial to reproduce - all it takes is main() { int fd = open("/dev/zero", O_RDONLY); char *p = mmap(NULL, 16384, PROT_READ|PROT_WRITE, MAP_PRIVATE|MAP_ANON, -1, 0); munmap(p + 8192, 8192); read(fd, p + 8192 - 128, 192); } which had been oopsing since March 1997. Says something about the quality of test coverage... ;-/ And while today sparc32 port is nearly dead, back in '97 it had been very much alive; in fact, sparc64 had only been in mainline for 3 months by that point... Cc: stable@kernel.org Fixes: v2.1.29 Signed-off-by: Al Viro Signed-off-by: David S. Miller Signed-off-by: Greg Kroah-Hartman

sparc64: only select COMPAT_BINFMT_ELF if BINFMT_ELF is set

2021-03-03T17:22:48Z

[ Upstream commit 80bddf5c93a99e11fc9faf7e4b575d01cecd45d3 ] Currently COMPAT on SPARC64 selects COMPAT_BINFMT_ELF unconditionally, even when BINFMT_ELF is not enabled. This causes a kconfig warning. Instead, just select COMPAT_BINFMT_ELF if BINFMT_ELF is enabled. This builds cleanly with no kconfig warnings. WARNING: unmet direct dependencies detected for COMPAT_BINFMT_ELF Depends on [n]: COMPAT [=y] && BINFMT_ELF [=n] Selected by [y]: - COMPAT [=y] && SPARC64 [=y] Fixes: 26b4c912185a ("sparc,sparc64: unify Kconfig files") Signed-off-by: Randy Dunlap Cc: "David S. Miller" Cc: sparclinux@vger.kernel.org Cc: Sam Ravnborg Signed-off-by: David S. Miller Signed-off-by: Sasha Levin