kernel.git/arch/powerpc/platforms/pseries, branch linux-4.14.y

powerpc/pseries: fix possible memory leak in ibmebus_bus_init()

2023-09-23T08:47:04Z

[ Upstream commit afda85b963c12947e298ad85d757e333aa40fd74 ] If device_register() returns error in ibmebus_bus_init(), name of kobject which is allocated in dev_set_name() called in device_add() is leaked. As comment of device_add() says, it should call put_device() to drop the reference count that was set in device_initialize() when it fails, so the name can be freed in kobject_cleanup(). Signed-off-by: ruanjinjie Signed-off-by: Michael Ellerman Link: https://msgid.link/20221110011929.3709774-1-ruanjinjie@huawei.com Signed-off-by: Sasha Levin

powerpc/pseries/lparcfg: add missing RTAS retry status handling

2023-03-11T15:26:40Z

[ Upstream commit 5d08633e5f6564b60f1cbe09af3af40a74d66431 ] The ibm,get-system-parameter RTAS function may return -2 or 990x, which indicate that the caller should try again. lparcfg's parse_system_parameter_string() ignores this, making it possible to intermittently report incorrect SPLPAR characteristics. Move the RTAS call into a coventional rtas_busy_delay()-based loop. Signed-off-by: Nathan Lynch Fixes: 1da177e4c3f4 ("Linux-2.6.12-rc2") Signed-off-by: Michael Ellerman Link: https://lore.kernel.org/r/20230125-b4-powerpc-rtas-queue-v3-4-26929c8cce78@linux.ibm.com Signed-off-by: Sasha Levin

powerpc/pseries: wire up rng during setup_arch()

2022-07-02T14:18:10Z

commit e561e472a3d441753bd012333b057f48fef1045b upstream. The platform's RNG must be available before random_init() in order to be useful for initial seeding, which in turn means that it needs to be called from setup_arch(), rather than from an init call. Fortunately, each platform already has a setup_arch function pointer, which means it's easy to wire this up. This commit also removes some noisy log messages that don't add much. Fixes: a489043f4626 ("powerpc/pseries: Implement arch_get_random_long() based on H_RANDOM") Cc: stable@vger.kernel.org # v3.13+ Signed-off-by: Jason A. Donenfeld Reviewed-by: Christophe Leroy Signed-off-by: Michael Ellerman Link: https://lore.kernel.org/r/20220611151015.548325-4-Jason@zx2c4.com Signed-off-by: Jason A. Donenfeld Signed-off-by: Greg Kroah-Hartman

powerpc/pseries: Stop calling printk in rtas_stop_self()

2021-05-22T08:57:37Z

[ Upstream commit ed8029d7b472369a010a1901358567ca3b6dbb0d ] RCU complains about us calling printk() from an offline CPU: ============================= WARNING: suspicious RCU usage 5.12.0-rc7-02874-g7cf90e481cb8 #1 Not tainted ----------------------------- kernel/locking/lockdep.c:3568 RCU-list traversed in non-reader section!! other info that might help us debug this: RCU used illegally from offline CPU! rcu_scheduler_active = 2, debug_locks = 1 no locks held by swapper/0/0. stack backtrace: CPU: 0 PID: 0 Comm: swapper/0 Not tainted 5.12.0-rc7-02874-g7cf90e481cb8 #1 Call Trace: dump_stack+0xec/0x144 (unreliable) lockdep_rcu_suspicious+0x124/0x144 __lock_acquire+0x1098/0x28b0 lock_acquire+0x128/0x600 _raw_spin_lock_irqsave+0x6c/0xc0 down_trylock+0x2c/0x70 __down_trylock_console_sem+0x60/0x140 vprintk_emit+0x1a8/0x4b0 vprintk_func+0xcc/0x200 printk+0x40/0x54 pseries_cpu_offline_self+0xc0/0x120 arch_cpu_idle_dead+0x54/0x70 do_idle+0x174/0x4a0 cpu_startup_entry+0x38/0x40 rest_init+0x268/0x388 start_kernel+0x748/0x790 start_here_common+0x1c/0x614 Which happens because by the time we get to rtas_stop_self() we are already offline. In addition the message can be spammy, and is not that helpful for users, so remove it. Signed-off-by: Michael Ellerman Link: https://lore.kernel.org/r/20210418135413.1204031-1-mpe@ellerman.id.au Signed-off-by: Sasha Levin

powerpc/pseries: extract host bridge from pci_bus prior to bus removal

2021-05-22T08:57:33Z

[ Upstream commit 38d0b1c9cec71e6d0f3bddef0bbce41d05a3e796 ] The pci_bus->bridge reference may no longer be valid after pci_bus_remove() resulting in passing a bad value to device_unregister() for the associated bridge device. Store the host_bridge reference in a separate variable prior to pci_bus_remove(). Fixes: 7340056567e3 ("powerpc/pci: Reorder pci bus/bridge unregistration during PHB removal") Signed-off-by: Tyrel Datwyler Signed-off-by: Michael Ellerman Link: https://lore.kernel.org/r/20210211182435.47968-1-tyreld@linux.ibm.com Signed-off-by: Sasha Levin

powerpc/pseries/dlpar: handle ibm, configure-connector delay status

2021-03-03T17:22:47Z

[ Upstream commit 768d70e19ba525debd571b36e6d0ab19956c63d7 ] dlpar_configure_connector() has two problems in its handling of ibm,configure-connector's return status: 1. When the status is -2 (busy, call again), we call ibm,configure-connector again immediately without checking whether to schedule, which can result in monopolizing the CPU. 2. Extended delay status (9900..9905) goes completely unhandled, causing the configuration to unnecessarily terminate. Fix both of these issues by using rtas_busy_delay(). Fixes: ab519a011caa ("powerpc/pseries: Kernel DLPAR Infrastructure") Signed-off-by: Nathan Lynch Reviewed-by: Tyrel Datwyler Signed-off-by: Michael Ellerman Link: https://lore.kernel.org/r/20210107025900.410369-1-nathanl@linux.ibm.com Signed-off-by: Sasha Levin

powerpc/pseries/hibernation: remove redundant cacheinfo update

2020-12-29T12:47:00Z

[ Upstream commit b866459489fe8ef0e92cde3cbd6bbb1af6c4e99b ] Partitions with cache nodes in the device tree can encounter the following warning on resume: CPU 0 already accounted in PowerPC,POWER9@0(Data) WARNING: CPU: 0 PID: 3177 at arch/powerpc/kernel/cacheinfo.c:197 cacheinfo_cpu_online+0x640/0x820 These calls to cacheinfo_cpu_offline/online have been redundant since commit e610a466d16a ("powerpc/pseries/mobility: rebuild cacheinfo hierarchy post-migration"). Fixes: e610a466d16a ("powerpc/pseries/mobility: rebuild cacheinfo hierarchy post-migration") Signed-off-by: Nathan Lynch Signed-off-by: Michael Ellerman Link: https://lore.kernel.org/r/20201207215200.1785968-25-nathanl@linux.ibm.com Signed-off-by: Sasha Levin

powerpc/pseries/hibernation: drop pseries_suspend_begin() from suspend ops

2020-12-29T12:47:00Z

[ Upstream commit 52719fce3f4c7a8ac9eaa191e8d75a697f9fbcbc ] There are three ways pseries_suspend_begin() can be reached: 1. When "mem" is written to /sys/power/state: kobj_attr_store() -> state_store() -> pm_suspend() -> suspend_devices_and_enter() -> pseries_suspend_begin() This never works because there is no way to supply a valid stream id using this interface, and H_VASI_STATE is called with a stream id of zero. So this call path is useless at best. 2. When a stream id is written to /sys/devices/system/power/hibernate. pseries_suspend_begin() is polled directly from store_hibernate() until the stream is in the "Suspending" state (i.e. the platform is ready for the OS to suspend execution): dev_attr_store() -> store_hibernate() -> pseries_suspend_begin() 3. When a stream id is written to /sys/devices/system/power/hibernate (continued). After #2, pseries_suspend_begin() is called once again from the pm core: dev_attr_store() -> store_hibernate() -> pm_suspend() -> suspend_devices_and_enter() -> pseries_suspend_begin() This is redundant because the VASI suspend state is already known to be Suspending. The begin() callback of platform_suspend_ops is optional, so we can simply remove that assignment with no loss of function. Fixes: 32d8ad4e621d ("powerpc/pseries: Partition hibernation support") Signed-off-by: Nathan Lynch Signed-off-by: Michael Ellerman Link: https://lore.kernel.org/r/20201207215200.1785968-18-nathanl@linux.ibm.com Signed-off-by: Sasha Levin

powerpc/64s: flush L1D after user accesses

2020-11-22T09:00:24Z

commit 9a32a7e78bd0cd9a9b6332cbdc345ee5ffd0c5de upstream. IBM Power9 processors can speculatively operate on data in the L1 cache before it has been completely validated, via a way-prediction mechanism. It is not possible for an attacker to determine the contents of impermissible memory using this method, since these systems implement a combination of hardware and software security measures to prevent scenarios where protected data could be leaked. However these measures don't address the scenario where an attacker induces the operating system to speculatively execute instructions using data that the attacker controls. This can be used for example to speculatively bypass "kernel user access prevention" techniques, as discovered by Anthony Steinhauser of Google's Safeside Project. This is not an attack by itself, but there is a possibility it could be used in conjunction with side-channels or other weaknesses in the privileged code to construct an attack. This issue can be mitigated by flushing the L1 cache between privilege boundaries of concern. This patch flushes the L1 cache after user accesses. This is part of the fix for CVE-2020-4788. Signed-off-by: Nicholas Piggin Signed-off-by: Daniel Axtens Signed-off-by: Greg Kroah-Hartman

powerpc/64s: flush L1D on kernel entry

2020-11-22T09:00:23Z

commit f79643787e0a0762d2409b7b8334e83f22d85695 upstream. IBM Power9 processors can speculatively operate on data in the L1 cache before it has been completely validated, via a way-prediction mechanism. It is not possible for an attacker to determine the contents of impermissible memory using this method, since these systems implement a combination of hardware and software security measures to prevent scenarios where protected data could be leaked. However these measures don't address the scenario where an attacker induces the operating system to speculatively execute instructions using data that the attacker controls. This can be used for example to speculatively bypass "kernel user access prevention" techniques, as discovered by Anthony Steinhauser of Google's Safeside Project. This is not an attack by itself, but there is a possibility it could be used in conjunction with side-channels or other weaknesses in the privileged code to construct an attack. This issue can be mitigated by flushing the L1 cache between privilege boundaries of concern. This patch flushes the L1 cache on kernel entry. This is part of the fix for CVE-2020-4788. Signed-off-by: Nicholas Piggin Signed-off-by: Daniel Axtens Signed-off-by: Greg Kroah-Hartman