Y2038 July 2018

y2038@lists.linaro.org

27 participants
31 discussions

[PATCH v3] generic/390: Add tests for inode timestamp policy

by Deepa Dinamani

The test helps to validate clamping and mount behaviors according to supported file system timestamp ranges. Note that the test can fail on 32-bit systems for a few file systems. This will be corrected when vfs is transitioned to use 64-bit timestamps. Signed-off-by: Deepa Dinamani <deepa.kernel(a)gmail.com> --- The branch of the kernel tree can be located at https://github.com/deepa-hub/vfs refs/heads/vfs_timestamp_policy The xfs_io patch to add utimes is at https://www.spinics.net/lists/linux-xfs/msg02952.html Changes since v2: * Refactored notrun handling * Updated comments Changes since v1: * Use xfs_io utimes command * Updated error handling * Reorganized code according to review comments common/rc | 48 +++++++++++++ tests/generic/390 | 192 ++++++++++++++++++++++++++++++++++++++++++++++++++ tests/generic/390.out | 2 + tests/generic/group | 1 + 4 files changed, 243 insertions(+) create mode 100755 tests/generic/390 create mode 100644 tests/generic/390.out diff --git a/common/rc b/common/rc index e3b54ec..17f025e 100644 --- a/common/rc +++ b/common/rc @@ -1960,6 +1960,51 @@ _run_aiodio() return $status } +# this test requires y2038 sysfs switch and filesystem +# timestamp ranges support. +_require_y2038() +{ + local device=${1:-$TEST_DEV} + local sysfsdir=/proc/sys/fs/fs-timestamp-check-on + + if [ ! -e $sysfsdir ]; then + _notrun "no kernel support for y2038 sysfs switch" + fi + + local tsmin tsmax + read tsmin tsmax <<<$(_filesystem_timestamp_range $device) + if [ $tsmin -eq -1 -a $tsmax -eq -1 ]; then + _notrun "filesystem $FSTYP timestamp bounds are unknown" + fi +} + +_filesystem_timestamp_range() +{ + device=${1:-$TEST_DEV} + case $FSTYP in + ext4) + if [ $(dumpe2fs -h $device 2>/dev/null | grep "Inode size:" | cut -d: -f2) -gt 128 ]; then + echo "-2147483648 15032385535" + else + echo "-2147483648 2147483647" + fi + ;; + + xfs) + echo "-2147483648 2147483647" + ;; + jfs) + echo "0 4294967295" + ;; + f2fs) + echo "-2147483648 2147483647" + ;; + *) + echo "-1 -1" + ;; + esac +} + # indicate whether YP/NIS is active or not # _yp_active() @@ -2070,6 +2115,9 @@ _require_xfs_io_command() echo $testio | egrep -q "Inappropriate ioctl" && \ _notrun "xfs_io $command support is missing" ;; + "utimes" ) + testio=`$XFS_IO_PROG -f -c "utimes" 0 0 0 0 $testfile 2>&1` + ;; *) testio=`$XFS_IO_PROG -c "$command help" 2>&1` esac diff --git a/tests/generic/390 b/tests/generic/390 new file mode 100755 index 0000000..f68b931 --- /dev/null +++ b/tests/generic/390 @@ -0,0 +1,192 @@ +#! /bin/bash +# FS QA Test 390 +# +# Tests to verify policy for filesystem timestamps for +# supported ranges: +# 1. Verify filesystem rw mount according to sysctl +# timestamp_supported. +# 2. Verify timestamp clamping for timestamps beyond max +# timestamp supported. +# +# Exit status 1: either or both tests above fail. +# Exit status 0: both the above tests pass. +# +#----------------------------------------------------------------------- +# Copyright (c) 2016 Deepa Dinamani. All Rights Reserved. +# +# This program is free software; you can redistribute it and/or +# modify it under the terms of the GNU General Public License as +# published by the Free Software Foundation. +# +# This program is distributed in the hope that it would be useful, +# but WITHOUT ANY WARRANTY; without even the implied warranty of +# MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the +# GNU General Public License for more details. +# +# You should have received a copy of the GNU General Public License +# along with this program; if not, write the Free Software Foundation, +# Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA +#----------------------------------------------------------------------- +# + +seq=`basename $0` +seqres=$RESULT_DIR/$seq +echo "QA output created by $seq" + +here=`pwd` +tmp=/tmp/$$ +status=1 # failure is the default! +trap "exit \$status" 0 1 2 3 15 + +# Get standard environment, filters and checks. +. ./common/rc +. ./common/filter +. ./common/attr + +# remove previous $seqres.full before test +rm -f $seqres.full + +# Prerequisites for the test run. +_supported_fs generic +_supported_os Linux +_require_scratch +_require_xfs_io_command utimes + +# Compare file timestamps obtained from stat +# with a given timestamp. +check_stat() +{ + file=$1 + timestamp=$2 + + stat_timestamp=`stat -c"%X;%Y" $file` + + prev_timestamp="$timestamp;$timestamp" + if [ $prev_timestamp != $stat_timestamp ]; then + echo "$prev_timestamp != $stat_timestamp" | tee -a $seqres.full + fi +} + +run_test_individual() +{ + file=$1 + timestamp=$2 + update_time=$3 + + #check if the time needs update + if [ $update_time -eq 1 ]; then + echo "Updating file: $file to timestamp `date -d @$timestamp`" >> $seqres.full + $XFS_IO_PROG -f -c "utimes $timestamp 0 $timestamp 0" $file + if [ $? -ne 0 ]; then + echo "Failed to update times on $file" | tee -a $seqres.full + fi + fi + + tsclamp=$(($timestamp>$tsmax?$tsmax:$timestamp)) + echo "Checking file: $file Updated timestamp is `date -d @$tsclamp`" >> $seqres.full + check_stat $file $tsclamp +} + +run_test() +{ + update_time=$1 + + n=1 + + for TIME in "${TIMESTAMPS[@]}" + do + #Run the test + run_test_individual ${SCRATCH_MNT}/test_$n $TIME $update_time + + #update iterator + ((n++)) + done +} + +_scratch_mkfs &>> $seqres.full 2>&1 || _fail "mkfs failed" +_require_y2038 $SCRATCH_DEV + +read tsmin tsmax <<<$(_filesystem_timestamp_range $SCRATCH_DEV) +echo min supported timestamp $tsmin $(date --date=@$tsmin) >> $seqres.full +echo max supported timestamp $tsmax $(date --date=@$tsmax) >> $seqres.full + +# Test timestamps array + +declare -a TIMESTAMPS=( + $tsmin + 0 + $tsmax + $((tsmax+1)) + 4294967295 + 8589934591 + 34359738367 +) + +# Max timestamp is hardcoded to Mon Jan 18 19:14:07 PST 2038 +sys_tsmax=2147483647 +echo "max timestamp that needs to be supported by fs for rw mount is" \ + "$((sys_tsmax+1)) $(date --date=@$((sys_tsmax+1)))" >> $seqres.full + +read ts_check <<<$(cat /proc/sys/fs/fs-timestamp-check-on) + +_scratch_mount +result=$? + +if [ $ts_check -ne 0 ]; then + echo "sysctl filesystem timestamp check is on" >> $seqres.full + # check for mount failure if the minimum requirement for max timestamp + # supported is not met. + if [ $sys_tsmax -ge $tsmax ]; then + if [ $result -eq 0 ]; then + echo "mount test failed" | tee -a $seqres.full + exit + fi + else + if [ $result -ne 0 ]; then + echo "failed to mount $SCRATCH_DEV" | tee -a $seqres.full + exit + fi + fi +else + # if sysctl switch is off then mount should succeed always. + echo "sysctl filesystem timestamp check is off" >> $seqres.full + if [ $result -ne 0 ]; then + echo "failed to mount $SCRATCH_DEV and timestamp check is off" >> $seqres.full + exit + fi +fi + +# Begin test case 1 +echo "In memory timestamps update test start" >> $seqres.full + +# update time on the file +update_time=1 + +run_test $update_time + +echo "In memory timestamps update complete" >> $seqres.full + +echo "Unmounting and mounting scratch $SCRATCH_MNT" >> $seqres.full + +# unmount and remount $SCRATCH_DEV +_scratch_cycle_mount + +# Begin test case 2 + +n=1 + +# Do not update time on the file this time, just read from disk +update_time=0 + +echo "On disk timestamps update test start" >> $seqres.full + +# Re-run test +run_test $update_time + +echo "On disk timestamps update test complete" >> $seqres.full + +echo "y2038 inode timestamp tests completed successfully" + +# success, all done +status=0 +exit diff --git a/tests/generic/390.out b/tests/generic/390.out new file mode 100644 index 0000000..82bd4eb --- /dev/null +++ b/tests/generic/390.out @@ -0,0 +1,2 @@ +QA output created by 390 +y2038 inode timestamp tests completed successfully diff --git a/tests/generic/group b/tests/generic/group index 08007d7..d137d01 100644 --- a/tests/generic/group +++ b/tests/generic/group @@ -392,3 +392,4 @@ 387 auto clone 388 auto log metadata 389 auto quick acl +390 auto quick rw -- 2.7.4

5 years

[PATCH 0/6] System call table generation support

by Firoz Khan

The goal of this patch series is to easily add/modify/delete a system call by changing entry in syscall.tbl file. No need to manually edit many files. The another goal of this patch series is to to unify the system call implementation across all the architectures. ARM, s390 and x86 architecuture does have the similar support. I leverage their implementation to come up with a generic solution. I have done the same support for work for ia64, m68k, microblaze, mips, parisc, powerpc, sh, sparc, and xtensa. But I started sending the patch for one architecuture for review. Below mentioned git repository contains more details. Git repo:- https://github.com/frzkhn/system_call_table_generator/ Finally, this is the ground work for solving the Y2038 issue. We need to change two dozen of system calls to solve Y2038 issue. So this implementation will help to easily modify from existing system call to Y2038 compatible system calls. Firoz Khan (6): alpha: Move __IGNORE* entries to non uapi header alpha: Add CONFIG_OSF4_COMPAT for compat syscall support alpha: Unify the not-implemented system call entry name alpha: Replace NR_SYSCALLS macro from asm/unistd.h alpha: Add system call table generation support alpha: uapi header and system call table file generation arch/alpha/Makefile | 3 + arch/alpha/include/asm/Kbuild | 3 +- arch/alpha/include/asm/unistd.h | 7 +- arch/alpha/include/uapi/asm/Kbuild | 2 + arch/alpha/include/uapi/asm/unistd.h | 489 --------------------------- arch/alpha/kernel/Makefile | 2 +- arch/alpha/kernel/entry.S | 4 +- arch/alpha/kernel/osf_sys.c | 9 +- arch/alpha/kernel/syscall.S | 20 ++ arch/alpha/kernel/syscalls/Makefile | 37 +++ arch/alpha/kernel/syscalls/syscall.tbl | 450 +++++++++++++++++++++++++ arch/alpha/kernel/syscalls/syscallhdr.sh | 33 ++ arch/alpha/kernel/syscalls/syscalltbl.sh | 28 ++ arch/alpha/kernel/systbls.S | 552 ------------------------------- 14 files changed, 589 insertions(+), 1050 deletions(-) delete mode 100644 arch/alpha/include/uapi/asm/unistd.h create mode 100644 arch/alpha/kernel/syscall.S create mode 100644 arch/alpha/kernel/syscalls/Makefile create mode 100644 arch/alpha/kernel/syscalls/syscall.tbl create mode 100644 arch/alpha/kernel/syscalls/syscallhdr.sh create mode 100644 arch/alpha/kernel/syscalls/syscalltbl.sh delete mode 100644 arch/alpha/kernel/systbls.S -- 2.7.4

5 years, 8 months

[PATCH v3 0/7] Introduce struct __kernel_timex

by Deepa Dinamani

The series introduces struct __kernel_timex as a substitute for the non y2038 safe struct timex. The series is based on the original series posted by Arnd Bergmann in [1]. The overview of the series is as below: 1. Prepare for the compat timex interfaces to be used unconditionally. 2. Introduce struct __kernel_timex. 3. Use struct __kernel_timex in place of struct timex. 4. Switch syscalls to use struct __kernel_timex. [1] https://sourceware.org/ml/libc-alpha/2015-05/msg00070.html Changes since v2: * Use only generic compat.h for riscv Changes since v1: * Fix riscv asm/compat.h to pick up generic compat types Deepa Dinamani (7): arm64: Make basic compat_* types always available sparc: Make thread_info.h available directly riscv: Delete asm/compat.h timex: prepare compat helpers for y2038 changes time: Add struct __kernel_timex timex: use __kernel_timex internally timex: change syscalls to use struct __kernel_timex arch/alpha/kernel/osf_sys.c | 2 +- arch/arm64/include/asm/compat.h | 22 ++++----- arch/riscv/include/asm/Kbuild | 1 + arch/riscv/include/asm/compat.h | 29 ------------ arch/sparc/include/asm/compat.h | 2 + drivers/ptp/ptp_clock.c | 2 +- include/asm-generic/compat.h | 8 +++- include/linux/compat.h | 33 -------------- include/linux/compat_time.h | 34 ++++++++++++++ include/linux/posix-clock.h | 2 +- include/linux/syscalls.h | 5 +-- include/linux/timex.h | 9 +++- include/uapi/linux/timex.h | 41 +++++++++++++++++ kernel/compat.c | 63 -------------------------- kernel/time/ntp.c | 12 ++--- kernel/time/ntp_internal.h | 2 +- kernel/time/posix-clock.c | 2 +- kernel/time/posix-timers.c | 14 ++---- kernel/time/posix-timers.h | 2 +- kernel/time/time.c | 80 ++++++++++++++++++++++++++++++--- kernel/time/timekeeping.c | 4 +- 21 files changed, 199 insertions(+), 170 deletions(-) delete mode 100644 arch/riscv/include/asm/compat.h base-commit: 526674536360a4c508e84f67314c2028e45e1bf2 -- 2.17.1 Cc: catalin.marinas(a)arm.com Cc: davem(a)davemloft.net Cc: linux-alpha(a)vger.kernel.org Cc: linux-api(a)vger.kernel.org Cc: linux-arch(a)vger.kernel.org Cc: linux-riscv(a)lists.infradead.org Cc: netdev(a)vger.kernel.org Cc: palmer(a)sifive.com

5 years, 8 months

[PATCH 1/3] hfs: stop using timespec based interfaces

by Arnd Bergmann

The native HFS timestamps overflow in year 2040, two years after the Unix y2038 overflow. However, the way that the conversion between on-disk timestamps and in-kernel timestamps was implemented, 64-bit machines actually ended up converting negative UTC timestamps (1902 through 1969) into times between 2038 and 2106. Rather than making all machines faithfully represent timestamps in the ancient past but break after 2040, this changes the file system to always use the unsigned UTC interpretation, reading back times between 1970 and 2106. Signed-off-by: Arnd Bergmann <arnd(a)arndb.de> --- fs/hfs/hfs_fs.h | 6 ++++-- fs/hfs/inode.c | 4 ++-- 2 files changed, 6 insertions(+), 4 deletions(-) diff --git a/fs/hfs/hfs_fs.h b/fs/hfs/hfs_fs.h index 6d0783e2e276..ff432931a5b1 100644 --- a/fs/hfs/hfs_fs.h +++ b/fs/hfs/hfs_fs.h @@ -245,6 +245,8 @@ extern void hfs_mark_mdb_dirty(struct super_block *sb); * Unix: unsigned lil-endian since 00:00 GMT, Jan. 1, 1970 * mac: unsigned big-endian since 00:00 GMT, Jan. 1, 1904 * + * We treat all timestamps before 1970 as times after 2038, so this + * actually works until year 2106 */ #define __hfs_u_to_mtime(sec) cpu_to_be32(sec + 2082844800U - sys_tz.tz_minuteswest * 60) #define __hfs_m_to_utime(sec) (be32_to_cpu(sec) - 2082844800U + sys_tz.tz_minuteswest * 60) @@ -252,9 +254,9 @@ extern void hfs_mark_mdb_dirty(struct super_block *sb); #define HFS_I(inode) (container_of(inode, struct hfs_inode_info, vfs_inode)) #define HFS_SB(sb) ((struct hfs_sb_info *)(sb)->s_fs_info) -#define hfs_m_to_utime(time) (struct timespec){ .tv_sec = __hfs_m_to_utime(time) } +#define hfs_m_to_utime(time) (struct timespec64){ .tv_sec = __hfs_m_to_utime(time) } #define hfs_u_to_mtime(time) __hfs_u_to_mtime((time).tv_sec) -#define hfs_mtime() __hfs_u_to_mtime(get_seconds()) +#define hfs_mtime() __hfs_u_to_mtime(ktime_get_real_seconds()) static inline const char *hfs_mdb_name(struct super_block *sb) { diff --git a/fs/hfs/inode.c b/fs/hfs/inode.c index 2a16111d312f..b3309b83371a 100644 --- a/fs/hfs/inode.c +++ b/fs/hfs/inode.c @@ -351,7 +351,7 @@ static int hfs_read_inode(struct inode *inode, void *data) inode->i_mode &= ~hsb->s_file_umask; inode->i_mode |= S_IFREG; inode->i_ctime = inode->i_atime = inode->i_mtime = - timespec_to_timespec64(hfs_m_to_utime(rec->file.MdDat)); + hfs_m_to_utime(rec->file.MdDat); inode->i_op = &hfs_file_inode_operations; inode->i_fop = &hfs_file_operations; inode->i_mapping->a_ops = &hfs_aops; @@ -362,7 +362,7 @@ static int hfs_read_inode(struct inode *inode, void *data) HFS_I(inode)->fs_blocks = 0; inode->i_mode = S_IFDIR | (S_IRWXUGO & ~hsb->s_dir_umask); inode->i_ctime = inode->i_atime = inode->i_mtime = - timespec_to_timespec64(hfs_m_to_utime(rec->dir.MdDat)); + hfs_m_to_utime(rec->dir.MdDat); inode->i_op = &hfs_dir_inode_operations; inode->i_fop = &hfs_dir_operations; break; -- 2.9.0

5 years, 8 months

[PATCH] vfs: replace current_kernel_time64 with ktime equivalent

by Arnd Bergmann

current_time is the last remaining caller of current_kernel_time64(), which is a wrapper around ktime_get_coarse_real_ts64(). This calls the latter directly for consistency with the rest of the kernel that is moving to the ktime_get_ family of time accessors, as now documented in Documentation/core-api/timekeeping.rst. An open questions is whether we may want to actually call the more accurate ktime_get_real_ts64() for file systems that save high-resolution timestamps in their on-disk format. This would add a small overhead to each update of the inode stamps but lead to inode timestamps to actually have a usable resolution better than one jiffy (1 to 10 milliseconds normally). Experiments on a variety of hardware platforms show a typical time of around 100 CPU cycles to read the cycle counter and calculate the accurate time from that. On old platforms without a cycle counter, this can be signiciantly higher, up to several microseconds to access a hardware clock, but those have become very rare by now. I traced the original addition of the current_kernel_time() call to set the nanosecond fields back to linux-2.5.48, where Andi Kleen added a patch with subject "nanosecond stat timefields". Andi explains that the motivation was to introduce as little overhead as possible back then. At this time, reading the clock hardware was also more expensive when most architectures did not have a cycle counter. One side effect of having more accurate inode timestamp would be having to write out the inode every time that mtime/ctime/atime get touched on most systems, whereas many file systems today only write it when the timestamps have changed, i.e. at most once per jiffy unless something else changes as well. That change would certainly be noticed in some workloads, which is enough reason to not do it without a good reason, regardless of the cost of reading the time. One thing we could still consider however would be to round the timestamps from current_time() to multiples of NSEC_PER_JIFFY, e.g. full milliseconds rather than having six or seven meaningless but confusing digits at the end of the timestamp. Signed-off-by: Arnd Bergmann <arnd(a)arndb.de> -- changes in v2: * wait for Documentation to get merged first, as Dave Chinner requested * rewrite changelog based on discussion --- fs/inode.c | 4 +++- 1 file changed, 3 insertions(+), 1 deletion(-) diff --git a/fs/inode.c b/fs/inode.c index 462eb50b096f..c2dbab9a7cf5 100644 --- a/fs/inode.c +++ b/fs/inode.c @@ -2105,7 +2105,9 @@ EXPORT_SYMBOL(timespec64_trunc); */ struct timespec64 current_time(struct inode *inode) { - struct timespec64 now = current_kernel_time64(); + struct timespec64 now; + + ktime_get_coarse_real_ts64(&now); if (unlikely(!inode->i_sb)) { WARN(1, "current_time() called with uninitialized super_block in the inode"); -- 2.18.0

5 years, 9 months

[PATCH v2 1/4] sh: dreamcast: rtc: push down rtc class ops into driver

by Arnd Bergmann

The dreamcast RTC support has an extra level of indirection to provide either the old read_persistent_clock/update_persistent_clock interface or the rtc-generic device for hctosys/systohc. Both do the same thing here, so we can do away with the abstraction and simply enable the RTC core code to take care of it. Signed-off-by: Arnd Bergmann <arnd(a)arndb.de> --- arch/sh/boards/mach-dreamcast/Makefile | 4 +- arch/sh/boards/mach-dreamcast/rtc.c | 39 +++++++++++++------ arch/sh/boards/mach-dreamcast/setup.c | 1 - arch/sh/configs/dreamcast_defconfig | 2 + arch/sh/include/mach-dreamcast/mach/sysasic.h | 1 - 5 files changed, 31 insertions(+), 16 deletions(-) diff --git a/arch/sh/boards/mach-dreamcast/Makefile b/arch/sh/boards/mach-dreamcast/Makefile index 7b97546c7e5f..62b024bc2a3e 100644 --- a/arch/sh/boards/mach-dreamcast/Makefile +++ b/arch/sh/boards/mach-dreamcast/Makefile @@ -2,5 +2,5 @@ # Makefile for the Sega Dreamcast specific parts of the kernel # -obj-y := setup.o irq.o rtc.o - +obj-y := setup.o irq.o +obj-$(CONFIG_RTC_DRV_GENERIC) += rtc.o diff --git a/arch/sh/boards/mach-dreamcast/rtc.c b/arch/sh/boards/mach-dreamcast/rtc.c index 061d65714fcc..4f168d8d2951 100644 --- a/arch/sh/boards/mach-dreamcast/rtc.c +++ b/arch/sh/boards/mach-dreamcast/rtc.c @@ -11,8 +11,9 @@ */ #include <linux/time.h> -#include <asm/rtc.h> -#include <asm/io.h> +#include <linux/rtc.h> +#include <linux/io.h> +#include <linux/platform_device.h> /* The AICA RTC has an Epoch of 1/1/1950, so we must subtract 20 years (in seconds) to get the standard Unix Epoch when getting the time, and add @@ -30,9 +31,10 @@ * * Grabs the current RTC seconds counter and adjusts it to the Unix Epoch. */ -static void aica_rtc_gettimeofday(struct timespec *ts) +static int aica_rtc_gettimeofday(struct device *dev, struct rtc_time *tm) { unsigned long val1, val2; + time64_t t; do { val1 = ((__raw_readl(AICA_RTC_SECS_H) & 0xffff) << 16) | @@ -42,10 +44,12 @@ static void aica_rtc_gettimeofday(struct timespec *ts) (__raw_readl(AICA_RTC_SECS_L) & 0xffff); } while (val1 != val2); - ts->tv_sec = val1 - TWENTY_YEARS; + /* normalize to 1970..2106 time range */ + t = (u32)(val1 - TWENTY_YEARS); - /* Can't get nanoseconds with just a seconds counter. */ - ts->tv_nsec = 0; + rtc_time64_to_tm(t, tm); + + return 0; } /** @@ -54,10 +58,11 @@ static void aica_rtc_gettimeofday(struct timespec *ts) * * Adjusts the given @tv to the AICA Epoch and sets the RTC seconds counter. */ -static int aica_rtc_settimeofday(const time_t secs) +static int aica_rtc_settimeofday(struct device *dev, struct rtc_time *tm) { unsigned long val1, val2; - unsigned long adj = secs + TWENTY_YEARS; + time64_t secs = rtc_tm_to_time64(tm); + u32 adj = secs + TWENTY_YEARS; do { __raw_writel((adj & 0xffff0000) >> 16, AICA_RTC_SECS_H); @@ -73,9 +78,19 @@ static int aica_rtc_settimeofday(const time_t secs) return 0; } -void aica_time_init(void) +static const struct rtc_class_ops rtc_generic_ops = { + .read_time = aica_rtc_gettimeofday, + .set_time = aica_rtc_settimeofday, +}; + +static int __init aica_time_init(void) { - rtc_sh_get_time = aica_rtc_gettimeofday; - rtc_sh_set_time = aica_rtc_settimeofday; -} + struct platform_device *pdev; + + pdev = platform_device_register_data(NULL, "rtc-generic", -1, + &rtc_generic_ops, + sizeof(rtc_generic_ops)); + return PTR_ERR_OR_ZERO(pdev); +} +arch_initcall(aica_time_init); diff --git a/arch/sh/boards/mach-dreamcast/setup.c b/arch/sh/boards/mach-dreamcast/setup.c index ad1a4db72e04..672c2ad8f8d5 100644 --- a/arch/sh/boards/mach-dreamcast/setup.c +++ b/arch/sh/boards/mach-dreamcast/setup.c @@ -30,7 +30,6 @@ static void __init dreamcast_setup(char **cmdline_p) { - board_time_init = aica_time_init; } static struct sh_machine_vector mv_dreamcast __initmv = { diff --git a/arch/sh/configs/dreamcast_defconfig b/arch/sh/configs/dreamcast_defconfig index 3f08dc54480b..1d27666c029f 100644 --- a/arch/sh/configs/dreamcast_defconfig +++ b/arch/sh/configs/dreamcast_defconfig @@ -70,3 +70,5 @@ CONFIG_PROC_KCORE=y CONFIG_TMPFS=y CONFIG_HUGETLBFS=y # CONFIG_CRYPTO_ANSI_CPRNG is not set +CONFIG_RTC_CLASS=y +CONFIG_RTC_DRV_GENERIC=y diff --git a/arch/sh/include/mach-dreamcast/mach/sysasic.h b/arch/sh/include/mach-dreamcast/mach/sysasic.h index 58f710e1ebc2..59effd1ed3e1 100644 --- a/arch/sh/include/mach-dreamcast/mach/sysasic.h +++ b/arch/sh/include/mach-dreamcast/mach/sysasic.h @@ -42,7 +42,6 @@ /* arch/sh/boards/mach-dreamcast/irq.c */ extern int systemasic_irq_demux(int); extern void systemasic_irq_init(void); -extern void aica_time_init(void); #endif /* __ASM_SH_DREAMCAST_SYSASIC_H */ -- 2.18.0

5 years, 9 months

[PATCH 1/2] [v2] hfs/hfsplus: follow MacOS time behavior

by Arnd Bergmann

According to the official documentation for HFS+ [1], inode timestamps are supposed to cover the time range from 1904 to 2040 as originally used in classic MacOS. The traditional Linux usage is to convert the timestamps into an unsigned 32-bit number based on the Unix epoch and from there to a time_t. On 32-bit systems, that wraps the time from 2038 to 1902, so the last two years of the valid time range become garbled. On 64-bit systems, all times before 1970 get turned into timestamps between 2038 and 2106, which is more convenient but also different from the documented behavior. Looking at the Darwin sources [2], it seems that MacOS is inconsistent in yet another way: all timestamps are wrapped around to a 32-bit unsigned number when written to the disk, but when read back, all numeric values lower than 2082844800U are assumed to be invalid, so we cannot represent the times before 1970 or the times after 2040. While all implementations seem to agree on the interpretation of values between 1970 and 2038, they often differ on the exact range they support when reading back values outside of the common range: MacOS (traditional): 1904-2040 Apple Documentation: 1904-2040 MacOS X source comments: 1970-2040 MacOS X source code: 1970-2038 32-bit Linux: 1902-2038 64-bit Linux: 1970-2106 hfsfuse: 1970-2040 hfsutils (32 bit, old libc) 1902-2038 hfsutils (32 bit, new libc) 1970-2106 hfsutils (64 bit) 1904-2040 hfsplus-utils 1904-2040 hfsexplorer 1904-2040 7-zip 1904-2040 This changes Linux over to mostly the same behavior as described in the code comment in MacOS X, disallowing all times before 1970 and after 2040, while still allowing times between 2038 and 2040 like most other implementations do. Most importantly, it means we can have the same behavior on 32-bit and 64-bit. Cc: stable(a)vger.kernel.org Link: [1] https://developer.apple.com/library/archive/technotes/tn/tn1150.html Link: [2] https://opensource.apple.com/source/hfs/hfs-407.30.1/core/MacOSStubs.c.auto… Suggested-by: Viacheslav Dubeyko <slava(a)dubeyko.com> Signed-off-by: Arnd Bergmann <arnd(a)arndb.de> --- v2: treat pre-1970 dates as invalid following MacOS X behavior, reword and expand changelog text --- fs/hfs/hfs_fs.h | 29 +++++++++++++++++++++++++---- fs/hfsplus/hfsplus_fs.h | 26 +++++++++++++++++++++++--- 2 files changed, 48 insertions(+), 7 deletions(-) diff --git a/fs/hfs/hfs_fs.h b/fs/hfs/hfs_fs.h index 6d0783e2e276..1af998fb522e 100644 --- a/fs/hfs/hfs_fs.h +++ b/fs/hfs/hfs_fs.h @@ -246,14 +246,35 @@ extern void hfs_mark_mdb_dirty(struct super_block *sb); * mac: unsigned big-endian since 00:00 GMT, Jan. 1, 1904 * */ -#define __hfs_u_to_mtime(sec) cpu_to_be32(sec + 2082844800U - sys_tz.tz_minuteswest * 60) -#define __hfs_m_to_utime(sec) (be32_to_cpu(sec) - 2082844800U + sys_tz.tz_minuteswest * 60) +static inline time64_t __hfs_m_to_utime(__be32 mt) +{ + time64_t ut = (u32)(be32_to_cpu(mt) - 2082844800U); + + /* + * Times past 2040-02-06 06:28 are assumed to be invalid, + * matching the MacOS behavior. + */ + if (ut > 2082844800U + UINT_MAX) + ut = 0; + + return ut + sys_tz.tz_minuteswest * 60; +} +static inline __be32 __hfs_u_to_mtime(time64_t ut) +{ + ut -= - sys_tz.tz_minuteswest * 60; + + /* + * MacOS wraps "invalid" times after 2040 when writing back, so + * let's do the same here. + */ + return cpu_to_be32(lower_32_bits(ut + 2082844800U)); +} #define HFS_I(inode) (container_of(inode, struct hfs_inode_info, vfs_inode)) #define HFS_SB(sb) ((struct hfs_sb_info *)(sb)->s_fs_info) -#define hfs_m_to_utime(time) (struct timespec){ .tv_sec = __hfs_m_to_utime(time) } -#define hfs_u_to_mtime(time) __hfs_u_to_mtime((time).tv_sec) +#define hfs_m_to_utime(time) (struct timespec){ .tv_sec = __hfs_m_to_utime(time) } +#define hfs_u_to_mtime(time) __hfs_u_to_mtime((time).tv_sec) #define hfs_mtime() __hfs_u_to_mtime(get_seconds()) static inline const char *hfs_mdb_name(struct super_block *sb) diff --git a/fs/hfsplus/hfsplus_fs.h b/fs/hfsplus/hfsplus_fs.h index d9255abafb81..7f0943e540a0 100644 --- a/fs/hfsplus/hfsplus_fs.h +++ b/fs/hfsplus/hfsplus_fs.h @@ -530,9 +530,29 @@ int hfsplus_submit_bio(struct super_block *sb, sector_t sector, void *buf, void **data, int op, int op_flags); int hfsplus_read_wrapper(struct super_block *sb); -/* time macros */ -#define __hfsp_mt2ut(t) (be32_to_cpu(t) - 2082844800U) -#define __hfsp_ut2mt(t) (cpu_to_be32(t + 2082844800U)) +/* time helpers */ +static inline time64_t __hfsp_mt2ut(__be32 mt) +{ + time64_t ut = (u32)(be32_to_cpu(mt) - 2082844800U); + + /* + * Times past 2040-02-06 06:28 are assumed to be invalid, + * matching the MacOS behavior. + */ + if (ut > 2082844800U + UINT_MAX) + ut = 0; + + return ut; +} + +static inline __be32 __hfsp_ut2mt(time64_t ut) +{ + /* + * MacOS wraps "invalid" times after 2040 when writing back, so + * let's do the same here. + */ + return cpu_to_be32(lower_32_bits(ut + 2082844800U)); +} /* compatibility */ #define hfsp_mt2ut(t) (struct timespec){ .tv_sec = __hfsp_mt2ut(t) } -- 2.9.0

5 years, 9 months

[PATCH] [RESEND] firewire: ohci: stop using get_seconds() for BUS_TIME

by Arnd Bergmann

The ohci driver uses the get_seconds() function to implement the 32-bit CSR_BUS_TIME register. This was added in 2010 commit a48777e03ad5 ("firewire: add CSR BUS_TIME support"). As get_seconds() returns a 32-bit value (on 32-bit architectures), it seems like a good fit for that register, but it is also deprecated because of the y2038/y2106 overflow problem, and should be replaced throughout the kernel with either ktime_get_real_seconds() or ktime_get_seconds(). I'm using the latter here, which uses monotonic time. This has the advantage of behaving better during concurrent settimeofday() updates or leap second adjustments and won't overflow a 32-bit integer, but the downside of using CLOCK_MONOTONIC instead of CLOCK_REALTIME is that the observed values are not related to external clocks. If we instead need UTC but can live with clock jumps or overflows, then we should use ktime_get_real_seconds() instead, retaining the existing behavior. Reviewed-by: Clemens Ladisch <clemens(a)ladisch.de> Signed-off-by: Arnd Bergmann <arnd(a)arndb.de> --- I notice that Stefan Richter has not been active on the mailing lists since February 2018. Andrew, could you pick it up in the meantime? --- drivers/firewire/ohci.c | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-) diff --git a/drivers/firewire/ohci.c b/drivers/firewire/ohci.c index 45c048751f3b..5125841ea338 100644 --- a/drivers/firewire/ohci.c +++ b/drivers/firewire/ohci.c @@ -1765,7 +1765,7 @@ static u32 update_bus_time(struct fw_ohci *ohci) if (unlikely(!ohci->bus_time_running)) { reg_write(ohci, OHCI1394_IntMaskSet, OHCI1394_cycle64Seconds); - ohci->bus_time = (lower_32_bits(get_seconds()) & ~0x7f) | + ohci->bus_time = (lower_32_bits(ktime_get_seconds()) & ~0x7f) | (cycle_time_seconds & 0x40); ohci->bus_time_running = true; } -- 2.9.0

5 years, 9 months

[PATCH 1/3] [v2] powerpc: mac: fix rtc read/write functions

by Arnd Bergmann

As Mathieu pointed out, my conversion to time64_t was incorrect and resulted in negative times to be read from the RTC. The problem is that during the conversion from a byte array to a time64_t, the 'unsigned char' variable holding the top byte gets turned into a negative signed 32-bit integer before being assigned to the 64-bit variable for any times after 1972. This changes the logic to cast to an unsigned 32-bit number first for the Macintosh time and then convert that to the Unix time, which then gives us a time in the documented 1904..2040 year range. I decided not to use the longer 1970..2106 range that other drivers use, for consistency with the literal interpretation of the register, but that could be easily changed if we decide we want to support any Mac after 2040. Just to be on the safe side, I'm also adding a WARN_ON that will trigger if either the year 2040 has come and is observed by this driver, or we run into an RTC that got set back to a pre-1970 date for some reason (the two are indistinguishable). For the RTC write functions, Andreas found another problem: both pmu_request() and cuda_request() are varargs functions, so changing the type of the arguments passed into them from 32 bit to 64 bit breaks the API for the set_rtc_time functions. This changes it back to 32 bits. The same code exists in arch/m68k/ and is patched in an identical way now in a separate patch. Fixes: 5bfd643583b2 ("powerpc: use time64_t in read_persistent_clock") Reported-by: Mathieu Malaterre <malat(a)debian.org> Reported-by: Andreas Schwab <schwab(a)linux-m68k.org> Signed-off-by: Arnd Bergmann <arnd(a)arndb.de> --- arch/powerpc/platforms/powermac/time.c | 29 ++++++++++++++++++++--------- 1 file changed, 20 insertions(+), 9 deletions(-) diff --git a/arch/powerpc/platforms/powermac/time.c b/arch/powerpc/platforms/powermac/time.c index 7c968e46736f..12e6e4d30602 100644 --- a/arch/powerpc/platforms/powermac/time.c +++ b/arch/powerpc/platforms/powermac/time.c @@ -42,7 +42,11 @@ #define DBG(x...) #endif -/* Apparently the RTC stores seconds since 1 Jan 1904 */ +/* + * Offset between Unix time (1970-based) and Mac time (1904-based). Cuda and PMU + * times wrap in 2040. If we need to handle later times, the read_time functions + * need to be changed to interpret wrapped times as post-2040. + */ #define RTC_OFFSET 2082844800 /* @@ -97,8 +101,11 @@ static time64_t cuda_get_time(void) if (req.reply_len != 7) printk(KERN_ERR "cuda_get_time: got %d byte reply\n", req.reply_len); - now = (req.reply[3] << 24) + (req.reply[4] << 16) - + (req.reply[5] << 8) + req.reply[6]; + now = (u32)((req.reply[3] << 24) + (req.reply[4] << 16) + + (req.reply[5] << 8) + req.reply[6]); + /* it's either after year 2040, or the RTC has gone backwards */ + WARN_ON(now < RTC_OFFSET); + return now - RTC_OFFSET; } @@ -106,10 +113,10 @@ static time64_t cuda_get_time(void) static int cuda_set_rtc_time(struct rtc_time *tm) { - time64_t nowtime; + u32 nowtime; struct adb_request req; - nowtime = rtc_tm_to_time64(tm) + RTC_OFFSET; + nowtime = lower_32_bits(rtc_tm_to_time64(tm) + RTC_OFFSET); if (cuda_request(&req, NULL, 6, CUDA_PACKET, CUDA_SET_TIME, nowtime >> 24, nowtime >> 16, nowtime >> 8, nowtime) < 0) @@ -140,8 +147,12 @@ static time64_t pmu_get_time(void) if (req.reply_len != 4) printk(KERN_ERR "pmu_get_time: got %d byte reply from PMU\n", req.reply_len); - now = (req.reply[0] << 24) + (req.reply[1] << 16) - + (req.reply[2] << 8) + req.reply[3]; + now = (u32)((req.reply[0] << 24) + (req.reply[1] << 16) + + (req.reply[2] << 8) + req.reply[3]); + + /* it's either after year 2040, or the RTC has gone backwards */ + WARN_ON(now < RTC_OFFSET); + return now - RTC_OFFSET; } @@ -149,10 +160,10 @@ static time64_t pmu_get_time(void) static int pmu_set_rtc_time(struct rtc_time *tm) { - time64_t nowtime; + u32 nowtime; struct adb_request req; - nowtime = rtc_tm_to_time64(tm) + RTC_OFFSET; + nowtime = lower_32_bits(rtc_tm_to_time64(tm) + RTC_OFFSET); if (pmu_request(&req, NULL, 5, PMU_SET_RTC, nowtime >> 24, nowtime >> 16, nowtime >> 8, nowtime) < 0) return -ENXIO; -- 2.9.0

5 years, 9 months

[PATCH v2 1/6] ext4: sysfs: print ext4_super_block fields as little-endian

by Arnd Bergmann

While working on extended rand for last_error/first_error timestamps, I noticed that the endianess is wrong, we access the little-endian fields in struct ext4_super_block as native-endian when we print them. This adds a special case in ext4_attr_show() and ext4_attr_store() to byteswap the superblock fields if needed. In older kernels, this code was part of super.c, it got moved to sysfs.c in linux-4.4. Cc: stable(a)vger.kernel.org Fixes: 52c198c6820f ("ext4: add sysfs entry showing whether the fs contains errors") Reviewed-by: Andreas Dilger <adilger(a)dilger.ca> Signed-off-by: Arnd Bergmann <arnd(a)arndb.de> --- fs/ext4/sysfs.c | 13 ++++++++++--- 1 file changed, 10 insertions(+), 3 deletions(-) diff --git a/fs/ext4/sysfs.c b/fs/ext4/sysfs.c index f34da0bb8f17..b970a200f20c 100644 --- a/fs/ext4/sysfs.c +++ b/fs/ext4/sysfs.c @@ -274,8 +274,12 @@ static ssize_t ext4_attr_show(struct kobject *kobj, case attr_pointer_ui: if (!ptr) return 0; - return snprintf(buf, PAGE_SIZE, "%u\n", - *((unsigned int *) ptr)); + if (a->attr_ptr == ptr_ext4_super_block_offset) + return snprintf(buf, PAGE_SIZE, "%u\n", + le32_to_cpup(ptr)); + else + return snprintf(buf, PAGE_SIZE, "%u\n", + *((unsigned int *) ptr)); case attr_pointer_atomic: if (!ptr) return 0; @@ -308,7 +312,10 @@ static ssize_t ext4_attr_store(struct kobject *kobj, ret = kstrtoul(skip_spaces(buf), 0, &t); if (ret) return ret; - *((unsigned int *) ptr) = t; + if (a->attr_ptr == ptr_ext4_super_block_offset) + *((__le32 *) ptr) = cpu_to_le32(t); + else + *((unsigned int *) ptr) = t; return len; case attr_inode_readahead: return inode_readahead_blks_store(sbi, buf, len); -- 2.9.0

5 years, 9 months

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Y2038 July 2018