/* * Helper function for splitting a string into an argv-like array. */ #include #include #include #include #include static int count_argc(const char *str) { int count = 0; bool was_space; for (was_space = true; *str; str++) { if (isspace(*str)) { was_space = true; } else if (was_space) { was_space = false; count++; } } return count; } /** * argv_free - free an argv * @argv - the argument vector to be freed * * Frees an argv and the strings it points to. */ void argv_free(char **argv) { argv--; kfree(argv[0]); kfree(argv); } EXPORT_SYMBOL(argv_free); /** * argv_split - split a string at whitespace, returning an argv * @gfp: the GFP mask used to allocate memory * @str: the string to be split * @argcp: returned argument count * * Returns an array of pointers to strings which are split out from * @str. This is performed by strictly splitting on white-space; no * quote processing is performed. Multiple whitespace characters are * considered to be a single argument separator. The returned array * is always NULL-terminated. Returns NULL on memory allocation * failure. * * The source string at `str' may be undergoing concurrent alteration via * userspace sysctl activity (at least). The argv_split() implementation * attempts to handle this gracefully by taking a local copy to work on. */ char **argv_split(gfp_t gfp, const char *str, int *argcp) { char *argv_str; bool was_space; char **argv, **argv_ret; int argc; argv_str = kstrndup(str, KMALLOC_MAX_SIZE - 1, gfp); if (!argv_str) return NULL; argc = count_argc(argv_str); argv = kmalloc(sizeof(*argv) * (argc + 2), gfp); if (!argv) { kfree(argv_str); return NULL; } *argv = argv_str; argv_ret = ++argv; for (was_space = true; *argv_str; argv_str++) { if (isspace(*argv_str)) { was_space = true; *argv_str = 0; } else if (was_space) { was_space = false; *argv++ = argv_str; } } *argv = NULL; if (argcp) *argcp = argc; return argv_ret; } EXPORT_SYMBOL(argv_split); mmitdiff
path: root/include/dt-bindings/reset/sun8i-h3-ccu.h
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authorArd Biesheuvel <ard.biesheuvel@linaro.org>2017-02-01 17:45:02 +0000
committerIngo Molnar <mingo@kernel.org>2017-02-01 21:17:49 +0100
commitc8f325a59cfc718d13a50fbc746ed9b415c25e92 (patch)
treed53fbdac9d0781e39a13b2ac6b2bd258cf3b4140 /include/dt-bindings/reset/sun8i-h3-ccu.h
parentbf29bddf0417a4783da3b24e8c9e017ac649326f (diff)
efi/fdt: Avoid FDT manipulation after ExitBootServices()
Some AArch64 UEFI implementations disable the MMU in ExitBootServices(), after which unaligned accesses to RAM are no longer supported. Commit: abfb7b686a3e ("efi/libstub/arm*: Pass latest memory map to the kernel") fixed an issue in the memory map handling of the stub FDT code, but inadvertently created an issue with such firmware, by moving some of the FDT manipulation to after the invocation of ExitBootServices(). Given that the stub's libfdt implementation uses the ordinary, accelerated string functions, which rely on hardware handling of unaligned accesses, manipulating the FDT with the MMU off may result in alignment faults. So fix the situation by moving the update_fdt_memmap() call into the callback function invoked by efi_exit_boot_services() right before it calls the ExitBootServices() UEFI service (which is arguably a better place for it anyway) Note that disabling the MMU in ExitBootServices() is not compliant with the UEFI spec, and carries great risk due to the fact that switching from cached to uncached memory accesses halfway through compiler generated code (i.e., involving a stack) can never be done in a way that is architecturally safe. Fixes: abfb7b686a3e ("efi/libstub/arm*: Pass latest memory map to the kernel") Signed-off-by: Ard Biesheuvel <ard.biesheuvel@linaro.org> Tested-by: Riku Voipio <riku.voipio@linaro.org> Cc: <stable@vger.kernel.org> Cc: mark.rutland@arm.com Cc: linux-efi@vger.kernel.org Cc: matt@codeblueprint.co.uk Cc: leif.lindholm@linaro.org Cc: linux-arm-kernel@lists.infradead.org Link: http://lkml.kernel.org/r/1485971102-23330-2-git-send-email-ard.biesheuvel@linaro.org Signed-off-by: Ingo Molnar <mingo@kernel.org>
Diffstat (limited to 'include/dt-bindings/reset/sun8i-h3-ccu.h')