| Message ID | 20230928-jag-sysctl_remove_empty_elem_drivers-v1-0-e59120fca9f9@samsung.com (mailing list archive) |
|---|---|
| State | New, archived |
| Headers | show |
On Thu, Sep 28, 2023 at 6:20 AM Joel Granados via B4 Relay <devnull+j.granados.samsung.com@kernel.org> wrote: > > From: Joel Granados <j.granados@samsung.com> > > This commit comes at the tail end of a greater effort to remove the > empty elements at the end of the ctl_table arrays (sentinels) which > will reduce the overall build time size of the kernel and run time > memory bloat by ~64 bytes per sentinel (further information Link : > https://lore.kernel.org/all/ZO5Yx5JFogGi%2FcBo@bombadil.infradead.org/) > > Remove sentinel from raid_table > > Signed-off-by: Joel Granados <j.granados@samsung.com> > --- > drivers/md/md.c | 3 +-- > 1 file changed, 1 insertion(+), 2 deletions(-) > > diff --git a/drivers/md/md.c b/drivers/md/md.c > index a104a025084d..3866d8f754a0 100644 > --- a/drivers/md/md.c > +++ b/drivers/md/md.c > @@ -304,8 +304,7 @@ static struct ctl_table raid_table[] = { > .maxlen = sizeof(int), > .mode = S_IRUGO|S_IWUSR, > .proc_handler = proc_dointvec, > - }, > - { } > + } > }; Please keep "}," as Greg suggested. Otherwise, Acked-by: Song Liu <song@kernel.org> Thanks, Song
Please change the prefix to "Drivers: hv:" in the subject line in the two patches. On Thu, Sep 28, 2023 at 03:21:39PM +0200, Joel Granados via B4 Relay wrote: > From: Joel Granados <j.granados@samsung.com> > > This commit comes at the tail end of a greater effort to remove the > empty elements at the end of the ctl_table arrays (sentinels) which > will reduce the overall build time size of the kernel and run time > memory bloat by ~64 bytes per sentinel (further information Link : > https://lore.kernel.org/all/ZO5Yx5JFogGi%2FcBo@bombadil.infradead.org/) > > Remove sentinel from hv_ctl_table > > Signed-off-by: Joel Granados <j.granados@samsung.com> > --- > drivers/hv/hv_common.c | 3 +-- > 1 file changed, 1 insertion(+), 2 deletions(-) > > diff --git a/drivers/hv/hv_common.c b/drivers/hv/hv_common.c > index ccad7bca3fd3..bc7d678030aa 100644 > --- a/drivers/hv/hv_common.c > +++ b/drivers/hv/hv_common.c > @@ -147,8 +147,7 @@ static struct ctl_table hv_ctl_table[] = { > .proc_handler = proc_dointvec_minmax, > .extra1 = SYSCTL_ZERO, > .extra2 = SYSCTL_ONE > - }, > - {} > + } Please keep the comma at the end. > }; > > static int hv_die_panic_notify_crash(struct notifier_block *self, > > -- > 2.30.2 >
Le 28/09/2023 à 15:21, Joel Granados via B4 Relay a écrit : > From: Joel Granados <j.granados@samsung.com> Automatic test fails on powerpc, see https://patchwork.ozlabs.org/project/linuxppc-dev/patch/20230928-jag-sysctl_remove_empty_elem_drivers-v1-15-e59120fca9f9@samsung.com/ Kernel attempted to read user page (1a111316) - exploit attempt? (uid: 0) BUG: Unable to handle kernel data access on read at 0x1a111316 Faulting instruction address: 0xc0545338 Oops: Kernel access of bad area, sig: 11 [#1] BE PAGE_SIZE=4K PowerPC 44x Platform Modules linked in: CPU: 0 PID: 1 Comm: swapper Not tainted 6.5.0-rc6-gdef13277bacb #1 Hardware name: amcc,bamboo 440GR Rev. B 0x422218d3 PowerPC 44x Platform NIP: c0545338 LR: c0548468 CTR: ffffffff REGS: c084fae0 TRAP: 0300 Not tainted (6.5.0-rc6-gdef13277bacb) MSR: 00021000 <CE,ME> CR: 84004288 XER: 00000000 DEAR: 1a111316 ESR: 00000000 GPR00: c0548468 c084fbd0 c0888000 c084fc99 00000000 c084fc7c 1a110316 000affff GPR08: ffffffff c084fd18 1a111316 04ffffff 22000282 00000000 c00027c0 00000000 GPR16: 00000000 00000000 c0040000 c003d544 00000001 c003eb2c 096023d4 00000000 GPR24: c0636502 c0636502 c084fc74 c0588510 c084fc68 c084fc7c c084fc99 00000002 NIP [c0545338] string+0x78/0x148 LR [c0548468] vsnprintf+0x3d8/0x824 Call Trace: [c084fbd0] [c084fc7c] 0xc084fc7c (unreliable) [c084fbe0] [c0548468] vsnprintf+0x3d8/0x824 [c084fc30] [c0072dec] vprintk_store+0x17c/0x4c8 [c084fcc0] [c007322c] vprintk_emit+0xf4/0x2a0 [c084fd00] [c0073d04] _printk+0x60/0x88 [c084fd40] [c01ab63c] sysctl_err+0x78/0xa4 [c084fd80] [c01ab404] __register_sysctl_table+0x6a0/0x6c4 [c084fde0] [c06a585c] __register_sysctl_init+0x30/0x78 [c084fe00] [c06a8cc8] tty_init+0x44/0x168 [c084fe30] [c00023c4] do_one_initcall+0x64/0x2a0 [c084fea0] [c068f060] kernel_init_freeable+0x184/0x230 [c084fee0] [c00027e4] kernel_init+0x24/0x124 [c084ff00] [c000f1fc] ret_from_kernel_user_thread+0x14/0x1c --- interrupt: 0 at 0x0 NIP: 00000000 LR: 00000000 CTR: 00000000 REGS: c084ff10 TRAP: 0000 Not tainted (6.5.0-rc6-gdef13277bacb) MSR: 00000000 <> CR: 00000000 XER: 00000000 GPR00: 00000000 00000000 00000000 00000000 00000000 00000000 00000000 00000000 GPR08: 00000000 00000000 00000000 00000000 00000000 00000000 00000000 00000000 GPR16: 00000000 00000000 00000000 00000000 00000000 00000000 00000000 00000000 GPR24: 00000000 00000000 00000000 00000000 00000000 00000000 00000000 00000000 NIP [00000000] 0x0 LR [00000000] 0x0 --- interrupt: 0 Code: 91610008 90e1000c 4bffd0b5 80010014 38210010 7c0803a6 4e800020 409d0008 99230000 38630001 38840001 4240ffd0 <7d2a20ae> 7f851840 5528063e 2c080000 ---[ end trace 0000000000000000 ]--- note: swapper[1] exited with irqs disabled Kernel panic - not syncing: Attempted to kill init! exitcode=0x0000000b > > What? > These commits remove the sentinel element (last empty element) from the > sysctl arrays of all the files under the "drivers/" directory that use a > sysctl array for registration. The merging of the preparation patches > (in https://lore.kernel.org/all/ZO5Yx5JFogGi%2FcBo@bombadil.infradead.org/) > to mainline allows us to just remove sentinel elements without changing > behavior (more info here [1]). > > These commits are part of a bigger set (here > https://github.com/Joelgranados/linux/tree/tag/sysctl_remove_empty_elem_V4) > that remove the ctl_table sentinel. Make the review process easier by > chunking the commits into manageable pieces. Each chunk can be reviewed > separately without noise from parallel sets. > > Now that the architecture chunk has been mostly reviewed [6], we send > the "drivers/" directory. Once this one is done, it will be follwed by > "fs/*", "kernel/*", "net/*" and miscellaneous. The final set will remove > the unneeded check for ->procname == NULL. > > Why? > By removing the sysctl sentinel elements we avoid kernel bloat as > ctl_table arrays get moved out of kernel/sysctl.c into their own > respective subsystems. This move was started long ago to avoid merge > conflicts; the sentinel removal bit came after Mathew Wilcox suggested > it to avoid bloating the kernel by one element as arrays moved out. This > patchset will reduce the overall build time size of the kernel and run > time memory bloat by about ~64 bytes per declared ctl_table array. I > have consolidated some links that shed light on the history of this > effort [2]. > > Testing: > * Ran sysctl selftests (./tools/testing/selftests/sysctl/sysctl.sh) > * Ran this through 0-day with no errors or warnings > > Size saving after removing all sentinels: > These are the bytes that we save after removing all the sentinels > (this plus all the other chunks). I included them to get an idea of > how much memory we are talking about. > * bloat-o-meter: > - The "yesall" configuration results save 9158 bytes > https://lore.kernel.org/all/20230621091000.424843-1-j.granados@samsung.com/ > - The "tiny" config + CONFIG_SYSCTL save 1215 bytes > https://lore.kernel.org/all/20230809105006.1198165-1-j.granados@samsung.com/ > * memory usage: > In memory savings are measured to be 7296 bytes. (here is how to > measure [3]) > > Size saving after this patchset: > * bloat-o-meter > - The "yesall" config saves 2432 bytes [4] > - The "tiny" config saves 64 bytes [5] > * memory usage: > In this case there were no bytes saved because I do not have any > of the drivers in the patch. To measure it comment the printk in > `new_dir` and uncomment the if conditional in `new_links` [3]. > > Comments/feedback greatly appreciated > > Best > Joel > > [1] > We are able to remove a sentinel table without behavioral change by > introducing a table_size argument in the same place where procname is > checked for NULL. The idea is for it to keep stopping when it hits > ->procname == NULL, while the sentinel is still present. And when the > sentinel is removed, it will stop on the table_size. You can go to > (https://lore.kernel.org/all/20230809105006.1198165-1-j.granados@samsung.com/) > for more information. > > [2] > Links Related to the ctl_table sentinel removal: > * Good summary from Luis sent with the "pull request" for the > preparation patches. > https://lore.kernel.org/all/ZO5Yx5JFogGi%2FcBo@bombadil.infradead.org/ > * Another very good summary from Luis. > https://lore.kernel.org/all/ZMFizKFkVxUFtSqa@bombadil.infradead.org/ > * This is a patch set that replaces register_sysctl_table with register_sysctl > https://lore.kernel.org/all/20230302204612.782387-1-mcgrof@kernel.org/ > * Patch set to deprecate register_sysctl_paths() > https://lore.kernel.org/all/20230302202826.776286-1-mcgrof@kernel.org/ > * Here there is an explicit expectation for the removal of the sentinel element. > https://lore.kernel.org/all/20230321130908.6972-1-frank.li@vivo.com > * The "ARRAY_SIZE" approach was mentioned (proposed?) in this thread > https://lore.kernel.org/all/20220220060626.15885-1-tangmeng@uniontech.com > > [3] > To measure the in memory savings apply this on top of this patchset. > > " > diff --git a/fs/proc/proc_sysctl.c b/fs/proc/proc_sysctl.c > index c88854df0b62..e0073a627bac 100644 > --- a/fs/proc/proc_sysctl.c > +++ b/fs/proc/proc_sysctl.c > @@ -976,6 +976,8 @@ static struct ctl_dir *new_dir(struct ctl_table_set *set, > table[0].procname = new_name; > table[0].mode = S_IFDIR|S_IRUGO|S_IXUGO; > init_header(&new->header, set->dir.header.root, set, node, table, 1); > + // Counts additional sentinel used for each new dir. > + printk("%ld sysctl saved mem kzalloc \n", sizeof(struct ctl_table)); > > return new; > } > @@ -1199,6 +1201,9 @@ static struct ctl_table_header *new_links(struct ctl_dir *dir, struct ctl_table_ > link_name += len; > link++; > } > + // Counts additional sentinel used for each new registration > + //if ((head->ctl_table + head->ctl_table_size)->procname) > + printk("%ld sysctl saved mem kzalloc \n", sizeof(struct ctl_table)); > init_header(links, dir->header.root, dir->header.set, node, link_table, > head->ctl_table_size); > links->nreg = nr_entries; > " > and then run the following bash script in the kernel: > > accum=0 > for n in $(dmesg | grep kzalloc | awk '{print $3}') ; do > echo $n > accum=$(calc "$accum + $n") > done > echo $accum > > [4] > add/remove: 0/0 grow/shrink: 0/21 up/down: 0/-2432 (-2432) > Function old new delta > xpc_sys_xpc_hb 192 128 -64 > xpc_sys_xpc 128 64 -64 > vrf_table 128 64 -64 > ucma_ctl_table 128 64 -64 > tty_table 192 128 -64 > sg_sysctls 128 64 -64 > scsi_table 128 64 -64 > random_table 448 384 -64 > raid_table 192 128 -64 > oa_table 192 128 -64 > mac_hid_files 256 192 -64 > iwcm_ctl_table 128 64 -64 > ipmi_table 128 64 -64 > hv_ctl_table 128 64 -64 > hpet_table 128 64 -64 > firmware_config_table 192 128 -64 > cdrom_table 448 384 -64 > balloon_table 128 64 -64 > parport_sysctl_template 912 720 -192 > parport_default_sysctl_table 584 136 -448 > parport_device_sysctl_template 776 136 -640 > Total: Before=429940038, After=429937606, chg -0.00% > > [5] > add/remove: 0/0 grow/shrink: 0/1 up/down: 0/-64 (-64) > Function old new delta > random_table 448 384 -64 > Total: Before=1885527, After=1885463, chg -0.00% > > [6] https://lore.kernel.org/all/20230913-jag-sysctl_remove_empty_elem_arch-v2-0-d1bd13a29bae@samsung.com/ > > Signed-off-by: Joel Granados <j.granados@samsung.com> > > --- > > --- > Joel Granados (15): > cdrom: Remove now superfluous sentinel element from ctl_table array > hpet: Remove now superfluous sentinel element from ctl_table array > xen: Remove now superfluous sentinel element from ctl_table array > tty: Remove now superfluous sentinel element from ctl_table array > scsi: Remove now superfluous sentinel element from ctl_table array > parport: Remove the now superfluous sentinel element from ctl_table array > macintosh: Remove the now superfluous sentinel element from ctl_table array > infiniband: Remove the now superfluous sentinel element from ctl_table array > char-misc: Remove the now superfluous sentinel element from ctl_table array > vrf: Remove the now superfluous sentinel element from ctl_table array > sgi-xp: Remove the now superfluous sentinel element from ctl_table array > fw loader: Remove the now superfluous sentinel element from ctl_table array > raid: Remove now superfluous sentinel element from ctl_table array > hyper-v/azure: Remove now superfluous sentinel element from ctl_table array > intel drm: Remove now superfluous sentinel element from ctl_table array > > drivers/base/firmware_loader/fallback_table.c | 3 +- > drivers/cdrom/cdrom.c | 3 +- > drivers/char/hpet.c | 3 +- > drivers/char/ipmi/ipmi_poweroff.c | 3 +- > drivers/char/random.c | 3 +- > drivers/gpu/drm/i915/i915_perf.c | 3 +- > drivers/hv/hv_common.c | 3 +- > drivers/infiniband/core/iwcm.c | 3 +- > drivers/infiniband/core/ucma.c | 3 +- > drivers/macintosh/mac_hid.c | 3 +- > drivers/md/md.c | 3 +- > drivers/misc/sgi-xp/xpc_main.c | 6 ++-- > drivers/net/vrf.c | 3 +- > drivers/parport/procfs.c | 42 ++++++++++++--------------- > drivers/scsi/scsi_sysctl.c | 3 +- > drivers/scsi/sg.c | 3 +- > drivers/tty/tty_io.c | 3 +- > drivers/xen/balloon.c | 3 +- > 18 files changed, 36 insertions(+), 60 deletions(-) > --- > base-commit: 0e945134b680040b8613e962f586d91b6d40292d > change-id: 20230927-jag-sysctl_remove_empty_elem_drivers-f034962a0d8c > > Best regards,
On Thu, Sep 28, 2023 at 03:21:36PM +0200, Joel Granados via B4 Relay wrote: > From: Joel Granados <j.granados@samsung.com> > > This commit comes at the tail end of a greater effort to remove the > empty elements at the end of the ctl_table arrays (sentinels) which > will reduce the overall build time size of the kernel and run time > memory bloat by ~64 bytes per sentinel (further information Link : > https://lore.kernel.org/all/ZO5Yx5JFogGi%2FcBo@bombadil.infradead.org/) > > Remove sentinel from xpc_sys_xpc_hb and xpc_sys_xpc > > Signed-off-by: Joel Granados <j.granados@samsung.com> > --- > drivers/misc/sgi-xp/xpc_main.c | 6 ++---- > 1 file changed, 2 insertions(+), 4 deletions(-) > > diff --git a/drivers/misc/sgi-xp/xpc_main.c b/drivers/misc/sgi-xp/xpc_main.c > index 6da509d692bb..c898092ff3ac 100644 > --- a/drivers/misc/sgi-xp/xpc_main.c > +++ b/drivers/misc/sgi-xp/xpc_main.c > @@ -109,8 +109,7 @@ static struct ctl_table xpc_sys_xpc_hb[] = { > .mode = 0644, > .proc_handler = proc_dointvec_minmax, > .extra1 = &xpc_hb_check_min_interval, > - .extra2 = &xpc_hb_check_max_interval}, > - {} > + .extra2 = &xpc_hb_check_max_interval} > }; > static struct ctl_table xpc_sys_xpc[] = { > { > @@ -120,8 +119,7 @@ static struct ctl_table xpc_sys_xpc[] = { > .mode = 0644, > .proc_handler = proc_dointvec_minmax, > .extra1 = &xpc_disengage_min_timelimit, > - .extra2 = &xpc_disengage_max_timelimit}, > - {} > + .extra2 = &xpc_disengage_max_timelimit} > }; > > static struct ctl_table_header *xpc_sysctl; > > -- > 2.30.2 > I assume you'll match the rest of the changes with regards to the trailing comma. Reviewed-by: Steve Wahl <steve.wahl@hpe.com>
On Thu, Sep 28, 2023 at 12:51:15PM -0500, Steve Wahl wrote: > On Thu, Sep 28, 2023 at 03:21:36PM +0200, Joel Granados via B4 Relay wrote: > > From: Joel Granados <j.granados@samsung.com> > > > > This commit comes at the tail end of a greater effort to remove the > > empty elements at the end of the ctl_table arrays (sentinels) which > > will reduce the overall build time size of the kernel and run time > > memory bloat by ~64 bytes per sentinel (further information Link : > > https://lore.kernel.org/all/ZO5Yx5JFogGi%2FcBo@bombadil.infradead.org/) > > > > Remove sentinel from xpc_sys_xpc_hb and xpc_sys_xpc > > > > Signed-off-by: Joel Granados <j.granados@samsung.com> > > --- > > drivers/misc/sgi-xp/xpc_main.c | 6 ++---- > > 1 file changed, 2 insertions(+), 4 deletions(-) > > > > diff --git a/drivers/misc/sgi-xp/xpc_main.c b/drivers/misc/sgi-xp/xpc_main.c > > index 6da509d692bb..c898092ff3ac 100644 > > --- a/drivers/misc/sgi-xp/xpc_main.c > > +++ b/drivers/misc/sgi-xp/xpc_main.c > > @@ -109,8 +109,7 @@ static struct ctl_table xpc_sys_xpc_hb[] = { > > .mode = 0644, > > .proc_handler = proc_dointvec_minmax, > > .extra1 = &xpc_hb_check_min_interval, > > - .extra2 = &xpc_hb_check_max_interval}, > > - {} > > + .extra2 = &xpc_hb_check_max_interval} > > }; > > static struct ctl_table xpc_sys_xpc[] = { > > { > > @@ -120,8 +119,7 @@ static struct ctl_table xpc_sys_xpc[] = { > > .mode = 0644, > > .proc_handler = proc_dointvec_minmax, > > .extra1 = &xpc_disengage_min_timelimit, > > - .extra2 = &xpc_disengage_max_timelimit}, > > - {} > > + .extra2 = &xpc_disengage_max_timelimit} > > }; > > > > static struct ctl_table_header *xpc_sysctl; > > > > -- > > 2.30.2 > > > > I assume you'll match the rest of the changes with regards to the > trailing comma. If you are refering to Greg's comments. yes. I'll send a V2 with the trailing comma. Best > > Reviewed-by: Steve Wahl <steve.wahl@hpe.com> > > -- > Steve Wahl, Hewlett Packard Enterprise
On Thu, Sep 28, 2023 at 03:26:16PM +0000, Wei Liu wrote: > Please change the prefix to "Drivers: hv:" in the subject line in the > two patches. > > On Thu, Sep 28, 2023 at 03:21:39PM +0200, Joel Granados via B4 Relay wrote: > > From: Joel Granados <j.granados@samsung.com> > > > > This commit comes at the tail end of a greater effort to remove the > > empty elements at the end of the ctl_table arrays (sentinels) which > > will reduce the overall build time size of the kernel and run time > > memory bloat by ~64 bytes per sentinel (further information Link : > > https://lore.kernel.org/all/ZO5Yx5JFogGi%2FcBo@bombadil.infradead.org/) > > > > Remove sentinel from hv_ctl_table > > > > Signed-off-by: Joel Granados <j.granados@samsung.com> > > --- > > drivers/hv/hv_common.c | 3 +-- > > 1 file changed, 1 insertion(+), 2 deletions(-) > > > > diff --git a/drivers/hv/hv_common.c b/drivers/hv/hv_common.c > > index ccad7bca3fd3..bc7d678030aa 100644 > > --- a/drivers/hv/hv_common.c > > +++ b/drivers/hv/hv_common.c > > @@ -147,8 +147,7 @@ static struct ctl_table hv_ctl_table[] = { > > .proc_handler = proc_dointvec_minmax, > > .extra1 = SYSCTL_ZERO, > > .extra2 = SYSCTL_ONE > > - }, > > - {} > > + } > > Please keep the comma at the end. My V2 will have this. > > > }; > > > > static int hv_die_panic_notify_crash(struct notifier_block *self, > > > > -- > > 2.30.2 > >
On Thu, Sep 28, 2023 at 03:26:16PM +0000, Wei Liu wrote: > Please change the prefix to "Drivers: hv:" in the subject line in the > two patches. I'll change the commit message for the 14/15 patch from "hyper-v/azure" to "Drivers: hv:". But I only see one patch that needs this. Which is the other one? best > > On Thu, Sep 28, 2023 at 03:21:39PM +0200, Joel Granados via B4 Relay wrote: > > From: Joel Granados <j.granados@samsung.com> > > > > This commit comes at the tail end of a greater effort to remove the > > empty elements at the end of the ctl_table arrays (sentinels) which > > will reduce the overall build time size of the kernel and run time > > memory bloat by ~64 bytes per sentinel (further information Link : > > https://lore.kernel.org/all/ZO5Yx5JFogGi%2FcBo@bombadil.infradead.org/) > > > > Remove sentinel from hv_ctl_table > > > > Signed-off-by: Joel Granados <j.granados@samsung.com> > > --- > > drivers/hv/hv_common.c | 3 +-- > > 1 file changed, 1 insertion(+), 2 deletions(-) > > > > diff --git a/drivers/hv/hv_common.c b/drivers/hv/hv_common.c > > index ccad7bca3fd3..bc7d678030aa 100644 > > --- a/drivers/hv/hv_common.c > > +++ b/drivers/hv/hv_common.c > > @@ -147,8 +147,7 @@ static struct ctl_table hv_ctl_table[] = { > > .proc_handler = proc_dointvec_minmax, > > .extra1 = SYSCTL_ZERO, > > .extra2 = SYSCTL_ONE > > - }, > > - {} > > + } > > Please keep the comma at the end. > > > }; > > > > static int hv_die_panic_notify_crash(struct notifier_block *self, > > > > -- > > 2.30.2 > >
On Thu, Sep 28, 2023 at 04:31:30PM +0000, Christophe Leroy wrote: > > > Le 28/09/2023 à 15:21, Joel Granados via B4 Relay a écrit : > > From: Joel Granados <j.granados@samsung.com> > > Automatic test fails on powerpc, see > https://patchwork.ozlabs.org/project/linuxppc-dev/patch/20230928-jag-sysctl_remove_empty_elem_drivers-v1-15-e59120fca9f9@samsung.com/ From this I got to this URL https://github.com/linuxppc/linux-snowpatch/actions/runs/6339718136/job/17221399242 and saw this message "sysctl table check failed: dev/tty/ No proc_handler". This means that we hit the check for entry->proc_handler in sysctl_check_table. > > Kernel attempted to read user page (1a111316) - exploit attempt? (uid: 0) > BUG: Unable to handle kernel data access on read at 0x1a111316 > Faulting instruction address: 0xc0545338 > Oops: Kernel access of bad area, sig: 11 [#1] > BE PAGE_SIZE=4K PowerPC 44x Platform > Modules linked in: > CPU: 0 PID: 1 Comm: swapper Not tainted 6.5.0-rc6-gdef13277bacb #1 > Hardware name: amcc,bamboo 440GR Rev. B 0x422218d3 PowerPC 44x Platform > NIP: c0545338 LR: c0548468 CTR: ffffffff > REGS: c084fae0 TRAP: 0300 Not tainted (6.5.0-rc6-gdef13277bacb) > MSR: 00021000 <CE,ME> CR: 84004288 XER: 00000000 > DEAR: 1a111316 ESR: 00000000 > GPR00: c0548468 c084fbd0 c0888000 c084fc99 00000000 c084fc7c 1a110316 > 000affff > GPR08: ffffffff c084fd18 1a111316 04ffffff 22000282 00000000 c00027c0 > 00000000 > GPR16: 00000000 00000000 c0040000 c003d544 00000001 c003eb2c 096023d4 > 00000000 > GPR24: c0636502 c0636502 c084fc74 c0588510 c084fc68 c084fc7c c084fc99 > 00000002 > NIP [c0545338] string+0x78/0x148 > LR [c0548468] vsnprintf+0x3d8/0x824 > Call Trace: > [c084fbd0] [c084fc7c] 0xc084fc7c (unreliable) > [c084fbe0] [c0548468] vsnprintf+0x3d8/0x824 > [c084fc30] [c0072dec] vprintk_store+0x17c/0x4c8 > [c084fcc0] [c007322c] vprintk_emit+0xf4/0x2a0 > [c084fd00] [c0073d04] _printk+0x60/0x88 > [c084fd40] [c01ab63c] sysctl_err+0x78/0xa4 > [c084fd80] [c01ab404] __register_sysctl_table+0x6a0/0x6c4 > [c084fde0] [c06a585c] __register_sysctl_init+0x30/0x78 > [c084fe00] [c06a8cc8] tty_init+0x44/0x168 > [c084fe30] [c00023c4] do_one_initcall+0x64/0x2a0 > [c084fea0] [c068f060] kernel_init_freeable+0x184/0x230 > [c084fee0] [c00027e4] kernel_init+0x24/0x124 > [c084ff00] [c000f1fc] ret_from_kernel_user_thread+0x14/0x1c I followed this trace and proc_handler is correctly defined in tty_table (struct ctl_table) in drivers/tty/tty_io.c:tty_init and there is not path that changes these values. Additionally, we then fail trying to print instead of continuing with the initialization. My conjecture is that this might be due to something different than tht sysctl register call. Does this happen consistenly or is this just a one off issue? To what branch are these patches being applied to? I'm going to post my V2 and keep working on this issue if it pops up again. Thx for the report Best > --- interrupt: 0 at 0x0 > NIP: 00000000 LR: 00000000 CTR: 00000000 > REGS: c084ff10 TRAP: 0000 Not tainted (6.5.0-rc6-gdef13277bacb) > MSR: 00000000 <> CR: 00000000 XER: 00000000 > > GPR00: 00000000 00000000 00000000 00000000 00000000 00000000 00000000 > 00000000 > GPR08: 00000000 00000000 00000000 00000000 00000000 00000000 00000000 > 00000000 > GPR16: 00000000 00000000 00000000 00000000 00000000 00000000 00000000 > 00000000 > GPR24: 00000000 00000000 00000000 00000000 00000000 00000000 00000000 > 00000000 > NIP [00000000] 0x0 > LR [00000000] 0x0 > --- interrupt: 0 > Code: 91610008 90e1000c 4bffd0b5 80010014 38210010 7c0803a6 4e800020 > 409d0008 99230000 38630001 38840001 4240ffd0 <7d2a20ae> 7f851840 > 5528063e 2c080000 > ---[ end trace 0000000000000000 ]--- > > note: swapper[1] exited with irqs disabled > Kernel panic - not syncing: Attempted to kill init! exitcode=0x0000000b > > > > > > What? > > These commits remove the sentinel element (last empty element) from the > > sysctl arrays of all the files under the "drivers/" directory that use a > > sysctl array for registration. The merging of the preparation patches > > (in https://lore.kernel.org/all/ZO5Yx5JFogGi%2FcBo@bombadil.infradead.org/) > > to mainline allows us to just remove sentinel elements without changing > > behavior (more info here [1]). <--- snip ---> > > drivers/macintosh/mac_hid.c | 3 +- > > drivers/md/md.c | 3 +- > > drivers/misc/sgi-xp/xpc_main.c | 6 ++-- > > drivers/net/vrf.c | 3 +- > > drivers/parport/procfs.c | 42 ++++++++++++--------------- > > drivers/scsi/scsi_sysctl.c | 3 +- > > drivers/scsi/sg.c | 3 +- > > drivers/tty/tty_io.c | 3 +- > > drivers/xen/balloon.c | 3 +- > > 18 files changed, 36 insertions(+), 60 deletions(-) > > --- > > base-commit: 0e945134b680040b8613e962f586d91b6d40292d > > change-id: 20230927-jag-sysctl_remove_empty_elem_drivers-f034962a0d8c > > > > Best regards,
Le 02/10/2023 à 10:47, Joel Granados a écrit : > On Thu, Sep 28, 2023 at 04:31:30PM +0000, Christophe Leroy wrote: > I followed this trace and proc_handler is correctly defined in tty_table > (struct ctl_table) in drivers/tty/tty_io.c:tty_init and there is not > path that changes these values. > Additionally, we then fail trying to print instead of continuing with > the initialization. My conjecture is that this might be due to something > different than tht sysctl register call. > > Does this happen consistenly or is this just a one off issue? Don't know. > > To what branch are these patches being applied to? As far as I understand from https://github.com/linuxppc/linux-snowpatch/commits/snowpatch/375319, it's being applied on https://git.kernel.org/pub/scm/linux/kernel/git/powerpc/linux.git/commit/?id=d774975 > > I'm going to post my V2 and keep working on this issue if it pops up > again. > Christophe
diff --git a/fs/proc/proc_sysctl.c b/fs/proc/proc_sysctl.c index c88854df0b62..e0073a627bac 100644 --- a/fs/proc/proc_sysctl.c +++ b/fs/proc/proc_sysctl.c @@ -976,6 +976,8 @@ static struct ctl_dir *new_dir(struct ctl_table_set *set, table[0].procname = new_name; table[0].mode = S_IFDIR|S_IRUGO|S_IXUGO; init_header(&new->header, set->dir.header.root, set, node, table, 1); + // Counts additional sentinel used for each new dir. + printk("%ld sysctl saved mem kzalloc \n", sizeof(struct ctl_table)); return new; } @@ -1199,6 +1201,9 @@ static struct ctl_table_header *new_links(struct ctl_dir *dir, struct ctl_table_ link_name += len; link++; } + // Counts additional sentinel used for each new registration + //if ((head->ctl_table + head->ctl_table_size)->procname) + printk("%ld sysctl saved mem kzalloc \n", sizeof(struct ctl_table)); init_header(links, dir->header.root, dir->header.set, node, link_table, head->ctl_table_size); links->nreg = nr_entries;