#include #include "notifier-error-inject.h" static int debugfs_errno_set(void *data, u64 val) { *(int *)data = clamp_t(int, val, -MAX_ERRNO, 0); return 0; } static int debugfs_errno_get(void *data, u64 *val) { *val = *(int *)data; return 0; } DEFINE_SIMPLE_ATTRIBUTE(fops_errno, debugfs_errno_get, debugfs_errno_set, "%lld\n"); static struct dentry *debugfs_create_errno(const char *name, umode_t mode, struct dentry *parent, int *value) { return debugfs_create_file(name, mode, parent, value, &fops_errno); } static int notifier_err_inject_callback(struct notifier_block *nb, unsigned long val, void *p) { int err = 0; struct notifier_err_inject *err_inject = container_of(nb, struct notifier_err_inject, nb); struct notifier_err_inject_action *action; for (action = err_inject->actions; action->name; action++) { if (action->val == val) { err = action->error; break; } } if (err) pr_info("Injecting error (%d) to %s\n", err, action->name); return notifier_from_errno(err); } struct dentry *notifier_err_inject_dir; EXPORT_SYMBOL_GPL(notifier_err_inject_dir); struct dentry *notifier_err_inject_init(const char *name, struct dentry *parent, struct notifier_err_inject *err_inject, int priority) { struct notifier_err_inject_action *action; umode_t mode = S_IFREG | S_IRUSR | S_IWUSR; struct dentry *dir; struct dentry *actions_dir; err_inject->nb.notifier_call = notifier_err_inject_callback; err_inject->nb.priority = priority; dir = debugfs_create_dir(name, parent); if (!dir) return ERR_PTR(-ENOMEM); actions_dir = debugfs_create_dir("actions", dir); if (!actions_dir) goto fail; for (action = err_inject->actions; action->name; action++) { struct dentry *action_dir; action_dir = debugfs_create_dir(action->name, actions_dir); if (!action_dir) goto fail; /* * Create debugfs r/w file containing action->error. If * notifier call chain is called with action->val, it will * fail with the error code */ if (!debugfs_create_errno("error", mode, action_dir, &action->error)) goto fail; } return dir; fail: debugfs_remove_recursive(dir); return ERR_PTR(-ENOMEM); } EXPORT_SYMBOL_GPL(notifier_err_inject_init); static int __init err_inject_init(void) { notifier_err_inject_dir = debugfs_create_dir("notifier-error-inject", NULL); if (!notifier_err_inject_dir) return -ENOMEM; return 0; } static void __exit err_inject_exit(void) { debugfs_remove_recursive(notifier_err_inject_dir); } module_init(err_inject_init); module_exit(err_inject_exit); MODULE_DESCRIPTION("Notifier error injection module"); MODULE_LICENSE("GPL"); MODULE_AUTHOR("Akinobu Mita "); earch' size='10' name='q' value=''/>
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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 /net/tipc/bcast.c
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 'net/tipc/bcast.c')