From df2f7cde73cb58c0e6a60f97d1cd6037138a45cd Mon Sep 17 00:00:00 2001 From: Vlastimil Babka Date: Mon, 7 Aug 2023 10:33:57 +0200 Subject: [PATCH 1/2] PM: hibernate: fix resume_store() return value when hibernation not available On a laptop with hibernation set up but not actively used, and with secure boot and lockdown enabled kernel, 6.5-rc1 gets stuck on boot with the following repeated messages: A start job is running for Resume from hibernation using device /dev/system/swap (24s / no limit) lockdown_is_locked_down: 25311154 callbacks suppressed Lockdown: systemd-hiberna: hibernation is restricted; see man kernel_lockdown.7 ... Checking the resume code leads to commit cc89c63e2fe3 ("PM: hibernate: move finding the resume device out of software_resume") which inadvertently changed the return value from resume_store() to 0 when !hibernation_available(). This apparently translates to userspace write() returning 0 as in number of bytes written, and userspace looping indefinitely in the attempt to write the intended value. Fix this by returning the full number of bytes that were to be written, as that's what was done before the commit. Fixes: cc89c63e2fe3 ("PM: hibernate: move finding the resume device out of software_resume") Signed-off-by: Vlastimil Babka Reviewed-by: Christoph Hellwig Acked-by: Greg Kroah-Hartman Signed-off-by: Rafael J. Wysocki --- kernel/power/hibernate.c | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-) diff --git a/kernel/power/hibernate.c b/kernel/power/hibernate.c index e1b4bfa938dd..2b4a946a6ff5 100644 --- a/kernel/power/hibernate.c +++ b/kernel/power/hibernate.c @@ -1166,7 +1166,7 @@ static ssize_t resume_store(struct kobject *kobj, struct kobj_attribute *attr, int error; if (!hibernation_available()) - return 0; + return n; if (len && buf[len-1] == '\n') len--; From 5e720f8c8c9d959283c3908bbf32a91a01a86547 Mon Sep 17 00:00:00 2001 From: =?UTF-8?q?Thomas=20Wei=C3=9Fschuh?= Date: Mon, 7 Aug 2023 08:37:45 +0200 Subject: [PATCH 2/2] cpufreq: amd-pstate: fix global sysfs attribute type MIME-Version: 1.0 Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 8bit In commit 3666062b87ec ("cpufreq: amd-pstate: move to use bus_get_dev_root()") the "amd_pstate" attributes where moved from a dedicated kobject to the cpu root kobject. While the dedicated kobject expects to contain kobj_attributes the root kobject needs device_attributes. As the changed arguments are not used by the callbacks it works most of the time. However CFI will detect this issue: [ 4947.849350] CFI failure at dev_attr_show+0x24/0x60 (target: show_status+0x0/0x70; expected type: 0x8651b1de) ... [ 4947.849409] Call Trace: [ 4947.849410] [ 4947.849411] ? __warn+0xcf/0x1c0 [ 4947.849414] ? dev_attr_show+0x24/0x60 [ 4947.849415] ? report_cfi_failure+0x4e/0x60 [ 4947.849417] ? handle_cfi_failure+0x14c/0x1d0 [ 4947.849419] ? __cfi_show_status+0x10/0x10 [ 4947.849420] ? handle_bug+0x4f/0x90 [ 4947.849421] ? exc_invalid_op+0x1a/0x60 [ 4947.849422] ? asm_exc_invalid_op+0x1a/0x20 [ 4947.849424] ? __cfi_show_status+0x10/0x10 [ 4947.849425] ? dev_attr_show+0x24/0x60 [ 4947.849426] sysfs_kf_seq_show+0xa6/0x110 [ 4947.849433] seq_read_iter+0x16c/0x4b0 [ 4947.849436] vfs_read+0x272/0x2d0 [ 4947.849438] ksys_read+0x72/0xe0 [ 4947.849439] do_syscall_64+0x76/0xb0 [ 4947.849440] ? do_user_addr_fault+0x252/0x650 [ 4947.849442] ? exc_page_fault+0x7a/0x1b0 [ 4947.849443] entry_SYSCALL_64_after_hwframe+0x72/0xdc Fixes: 3666062b87ec ("cpufreq: amd-pstate: move to use bus_get_dev_root()") Reported-by: Jannik Glückert Closes: https://bugzilla.kernel.org/show_bug.cgi?id=217765 Link: https://lore.kernel.org/lkml/c7f1bf9b-b183-bf6e-1cbb-d43f72494083@gmail.com/ Cc: All applicable Signed-off-by: Thomas Weißschuh Reviewed-by: Greg Kroah-Hartman Reviewed-by: Nathan Chancellor Signed-off-by: Rafael J. Wysocki --- drivers/cpufreq/amd-pstate.c | 10 +++++----- 1 file changed, 5 insertions(+), 5 deletions(-) diff --git a/drivers/cpufreq/amd-pstate.c b/drivers/cpufreq/amd-pstate.c index 81fba0dcbee9..9a1e194d5cf8 100644 --- a/drivers/cpufreq/amd-pstate.c +++ b/drivers/cpufreq/amd-pstate.c @@ -1012,8 +1012,8 @@ static int amd_pstate_update_status(const char *buf, size_t size) return 0; } -static ssize_t show_status(struct kobject *kobj, - struct kobj_attribute *attr, char *buf) +static ssize_t status_show(struct device *dev, + struct device_attribute *attr, char *buf) { ssize_t ret; @@ -1024,7 +1024,7 @@ static ssize_t show_status(struct kobject *kobj, return ret; } -static ssize_t store_status(struct kobject *a, struct kobj_attribute *b, +static ssize_t status_store(struct device *a, struct device_attribute *b, const char *buf, size_t count) { char *p = memchr(buf, '\n', count); @@ -1043,7 +1043,7 @@ cpufreq_freq_attr_ro(amd_pstate_lowest_nonlinear_freq); cpufreq_freq_attr_ro(amd_pstate_highest_perf); cpufreq_freq_attr_rw(energy_performance_preference); cpufreq_freq_attr_ro(energy_performance_available_preferences); -define_one_global_rw(status); +static DEVICE_ATTR_RW(status); static struct freq_attr *amd_pstate_attr[] = { &amd_pstate_max_freq, @@ -1062,7 +1062,7 @@ static struct freq_attr *amd_pstate_epp_attr[] = { }; static struct attribute *pstate_global_attributes[] = { - &status.attr, + &dev_attr_status.attr, NULL };