kernel/drivers/base, branch linux-4.17.y

x86/speculation/l1tf: Add sysfs reporting for l1tf

2018-08-15T16:10:59Z

commit 17dbca119312b4e8173d4e25ff64262119fcef38 upstream L1TF core kernel workarounds are cheap and normally always enabled, However they still should be reported in sysfs if the system is vulnerable or mitigated. Add the necessary CPU feature/bug bits. - Extend the existing checks for Meltdowns to determine if the system is vulnerable. All CPUs which are not vulnerable to Meltdown are also not vulnerable to L1TF - Check for 32bit non PAE and emit a warning as there is no practical way for mitigation due to the limited physical address bits - If the system has more than MAX_PA/2 physical memory the invert page workarounds don't protect the system against the L1TF attack anymore, because an inverted physical address will also point to valid memory. Print a warning in this case and report that the system is vulnerable. Add a function which returns the PFN limit for the L1TF mitigation, which will be used in follow up patches for sanity and range checks. [ tglx: Renamed the CPU feature bit to L1TF_PTEINV ] Signed-off-by: Andi Kleen Signed-off-by: Thomas Gleixner Reviewed-by: Josh Poimboeuf Acked-by: Dave Hansen Signed-off-by: Greg Kroah-Hartman

driver core: Partially revert "driver core: correct device's shutdown order"

2018-07-28T05:57:17Z

commit 722e5f2b1eec7de61117b7c0a7914761e3da2eda upstream. Commit 52cdbdd49853 (driver core: correct device's shutdown order) introduced a regression by breaking device shutdown on some systems. Namely, the devices_kset_move_last() call in really_probe() added by that commit is a mistake as it may cause parents to follow children in the devices_kset list which then causes shutdown to fail. For example, if a device has children before really_probe() is called for it (which is not uncommon), that call will cause it to be reordered after the children in the devices_kset list and the ordering of that list will not reflect the correct device shutdown order any more. Also it causes the devices_kset list to be constantly reordered until all drivers have been probed which is totally pointless overhead in the majority of cases and it only covered an issue with system shutdown, while system-wide suspend/resume potentially had the same issue on the affected platforms (which was not covered). Moreover, the shutdown issue originally addressed by the change in really_probe() made by commit 52cdbdd49853 is not present in 4.18-rc any more, since dra7 started to use the sdhci-omap driver which doesn't disable any regulators during shutdown, so the really_probe() part of commit 52cdbdd49853 can be safely reverted. [The original issue was related to the omap_hsmmc driver used by dra7 previously.] For the above reasons, revert the really_probe() modifications made by commit 52cdbdd49853. The other code changes made by commit 52cdbdd49853 are useful and they need not be reverted. Fixes: 52cdbdd49853 (driver core: correct device's shutdown order) Link: https://lore.kernel.org/lkml/CAFgQCTt7VfqM=UyCnvNFxrSw8Z6cUtAi3HUwR4_xPAc03SgHjQ@mail.gmail.com/ Reported-by: Pingfan Liu Tested-by: Pingfan Liu Reviewed-by: Kishon Vijay Abraham I Signed-off-by: Rafael J. Wysocki Cc: stable Signed-off-by: Greg Kroah-Hartman

PM / core: Fix supplier device runtime PM usage counter imbalance

2018-07-03T09:26:47Z

commit 47e5abfb546a3ace23a77453dc2e9db92704c5ac upstream. If a device link is added via device_link_add() by the driver of the link's consumer device, the supplier's runtime PM usage counter is going to be dropped by the pm_runtime_put_suppliers() call in driver_probe_device(). However, in that case it is not incremented unless the supplier driver is already present and the link is not stateless. That leads to a runtime PM usage counter imbalance for the supplier device in a few cases. To prevent that from happening, bump up the supplier runtime PM usage counter in device_link_add() for all links with the DL_FLAG_PM_RUNTIME flag set that are added at the consumer probe time. Use pm_runtime_get_noresume() for that as the callers of device_link_add() who want the supplier to be resumed by it are expected to pass DL_FLAG_RPM_ACTIVE in flags to it anyway, but additionally resume the supplier if the link is added during consumer driver probe to retain the existing behavior for the callers depending on it. Fixes: 21d5c57b3726 (PM / runtime: Use device links) Reported-by: Ulf Hansson Reviewed-by: Ulf Hansson Tested-by: Marek Szyprowski Cc: 4.10+ # 4.10+ Signed-off-by: Rafael J. Wysocki Signed-off-by: Greg Kroah-Hartman

PM / Domains: Fix error path during attach in genpd

2018-07-03T09:26:46Z

commit 72038df3c580c4c326b83c86149d7ac34007532a upstream. In case the PM domain fails to be powered on in genpd_dev_pm_attach(), it returns -EPROBE_DEFER, but keeping the device attached to its PM domain. This leads to problems when the next attempt to attach is re-tried. More precisely, in that situation an -EEXIST error code is returned, because the device already has its PM domain pointer assigned, from the first attempt. Now, because of the sloppy error handling by the existing callers of dev_pm_domain_attach(), probing is allowed to continue when -EEXIST is returned. However, in such case there are no guarantees that the PM domain is powered on by genpd, which may lead to hangs when buses/drivers tried to access their devices. Let's fix this behaviour, simply by detaching the device when powering on fails in genpd_dev_pm_attach(). Cc: v4.11+ # v4.11+ Signed-off-by: Ulf Hansson Signed-off-by: Rafael J. Wysocki Signed-off-by: Greg Kroah-Hartman

driver core: Don't ignore class_dir_create_and_add() failure.

2018-06-25T23:51:22Z

commit 84d0c27d6233a9ba0578b20f5a09701eb66cee42 upstream. syzbot is hitting WARN() at kernfs_add_one() [1]. This is because kernfs_create_link() is confused by previous device_add() call which continued without setting dev->kobj.parent field when get_device_parent() failed by memory allocation fault injection. Fix this by propagating the error from class_dir_create_and_add() to the calllers of get_device_parent(). [1] https://syzkaller.appspot.com/bug?id=fae0fb607989ea744526d1c082a5b8de6529116f Signed-off-by: Tetsuo Handa Reported-by: syzbot Cc: Greg Kroah-Hartman Cc: stable Signed-off-by: Greg Kroah-Hartman

mm/memory_hotplug: fix leftover use of struct page during hotplug

2018-05-26T01:12:11Z

The case of a new numa node got missed in avoiding using the node info from page_struct during hotplug. In this path we have a call to register_mem_sect_under_node (which allows us to specify it is hotplug so don't change the node), via link_mem_sections which unfortunately does not. Fix is to pass check_nid through link_mem_sections as well and disable it in the new numa node path. Note the bug only 'sometimes' manifests depending on what happens to be in the struct page structures - there are lots of them and it only needs to match one of them. The result of the bug is that (with a new memory only node) we never successfully call register_mem_sect_under_node so don't get the memory associated with the node in sysfs and meminfo for the node doesn't report it. It came up whilst testing some arm64 hotplug patches, but appears to be universal. Whilst I'm triggering it by removing then reinserting memory to a node with no other elements (thus making the node disappear then appear again), it appears it would happen on hotplugging memory where there was none before and it doesn't seem to be related the arm64 patches. These patches call __add_pages (where most of the issue was fixed by Pavel's patch). If there is a node at the time of the __add_pages call then all is well as it calls register_mem_sect_under_node from there with check_nid set to false. Without a node that function returns having not done the sysfs related stuff as there is no node to use. This is expected but it is the resulting path that fails... Exact path to the problem is as follows: mm/memory_hotplug.c: add_memory_resource() The node is not online so we enter the 'if (new_node)' twice, on the second such block there is a call to link_mem_sections which calls into drivers/node.c: link_mem_sections() which calls drivers/node.c: register_mem_sect_under_node() which calls get_nid_for_pfn and keeps trying until the output of that matches the expected node (passed all the way down from add_memory_resource) It is effectively the same fix as the one referred to in the fixes tag just in the code path for a new node where the comments point out we have to rerun the link creation because it will have failed in register_new_memory (as there was no node at the time). (actually that comment is wrong now as we don't have register_new_memory any more it got renamed to hotplug_memory_register in Pavel's patch). Link: http://lkml.kernel.org/r/20180504085311.1240-1-Jonathan.Cameron@huawei.com Fixes: fc44f7f9231a ("mm/memory_hotplug: don't read nid from struct page during hotplug") Signed-off-by: Jonathan Cameron Reviewed-by: Pavel Tatashin Acked-by: Michal Hocko Signed-off-by: Andrew Morton Signed-off-by: Linus Torvalds

Merge tag 'pm-4.17-rc7' of git://git.kernel.org/pub/scm/linux/kernel/git/rafael/linux-pm

2018-05-24T15:49:56Z

Pull power management fix from Rafael Wysocki: "Fix a regression from the 4.15 cycle that caused the system suspend and resume overhead to increase on many systems and triggered more serious problems on some of them (Rafael Wysocki)" * tag 'pm-4.17-rc7' of git://git.kernel.org/pub/scm/linux/kernel/git/rafael/linux-pm: PM / core: Fix direct_complete handling for devices with no callbacks

PM / core: Fix direct_complete handling for devices with no callbacks

2018-05-22T12:50:11Z

Commit 08810a4119aa (PM / core: Add NEVER_SKIP and SMART_PREPARE driver flags) inadvertently prevented the power.direct_complete flag from being set for devices without PM callbacks and with disabled runtime PM which also prevents power.direct_complete from being set for their parents. That led to problems including a resume crash on HP ZBook 14u. Restore the previous behavior by causing power.direct_complete to be set for those devices again, but do that in a more direct way to avoid overlooking that case in the future. Link: https://bugzilla.kernel.org/show_bug.cgi?id=199693 Fixes: 08810a4119aa (PM / core: Add NEVER_SKIP and SMART_PREPARE driver flags) Reported-by: Thomas Martitz Tested-by: Thomas Martitz Cc: 4.15+ # 4.15+ Signed-off-by: Rafael J. Wysocki Reviewed-by: Ulf Hansson Reviewed-by: Johan Hovold

x86/bugs: Expose /sys/../spec_store_bypass

2018-05-03T11:55:47Z

Add the sysfs file for the new vulerability. It does not do much except show the words 'Vulnerable' for recent x86 cores. Intel cores prior to family 6 are known not to be vulnerable, and so are some Atoms and some Xeon Phi. It assumes that older Cyrix, Centaur, etc. cores are immune. Signed-off-by: Konrad Rzeszutek Wilk Signed-off-by: Thomas Gleixner Reviewed-by: Borislav Petkov Reviewed-by: Ingo Molnar

Merge tag 'driver-core-4.17-rc3' of git://git.kernel.org/pub/scm/linux/kernel/git/gregkh/driver-core

2018-04-27T17:12:20Z

Pull driver core fixes from Greg Kroah-Hartman: "Here are some small driver core and firmware fixes for 4.17-rc3 There's a kobject WARN() removal to make syzkaller a lot happier about some "normal" error paths that it keeps hitting, which should reduce the number of false-positives we have been getting recently. There's also some fimware test and documentation fixes, and the coredump() function signature change that needed to happen after -rc1 before drivers started to take advantage of it. All of these have been in linux-next with no reported issues" * tag 'driver-core-4.17-rc3' of git://git.kernel.org/pub/scm/linux/kernel/git/gregkh/driver-core: firmware: some documentation fixes selftests:firmware: fixes a call to a wrong function name kobject: don't use WARN for registration failures firmware: Fix firmware documentation for recent file renames test_firmware: fix setting old custom fw path back on exit, second try test_firmware: Install all scripts drivers: change struct device_driver::coredump() return type to void