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Marussi</a><ul><li><a href="/lkml/2024/1/30/861">Ulf Hansson</a><ul><li><a href="/lkml/2024/1/30/1395">Cristian Marussi</a><ul><li><a href="/lkml/2024/1/31/672">Ulf Hansson</a><ul><li><a href="/lkml/2024/1/31/696">Sudeep Holla</a></li></ul></li></ul></li></ul></li><li><a href="/lkml/2024/1/31/1067">Sudeep Holla</a></li><li><a href="/lkml/2024/2/13/566">Ulf Hansson</a></li></ul></li></ul><div class="threadlist">Patch in this message</div><ul class="threadlist"><li><a href="/lkml/diff/2024/1/25/1045/1">Get diff 1</a></li></ul></td><td width="32" rowspan="2" class="c" valign="top"><img src="/images/icornerl.gif" width="32" height="32" alt="/" /></td><td class="c" rowspan="2" valign="top" style="padding-top: 1em"><table><tr><td><table><tr><td class="lp">From</td><td class="rp" itemprop="author">Cristian Marussi <></td></tr><tr><td class="lp">Subject</td><td class="rp" itemprop="name">[PATCH] pmdomain: arm: Fix NULL dereference on scmi_perf_domain removal</td></tr><tr><td class="lp">Date</td><td class="rp" itemprop="datePublished">Thu, 25 Jan 2024 19:17:56 +0000</td></tr></table></td><td></td></tr></table><pre itemprop="articleBody">On unloading of the scmi_perf_domain module got the below splat, when in<br />the DT provided to the system under test the '#power-domain-cells' property<br />was missing.<br />Indeed, this particular setup causes the probe to bail out early without<br />giving any error, so that, then, the removal code is run on unload, but<br />without all the expected initialized structures in place.<br /><br />Add a check and bail out early on remove too.<br /><br />Unable to handle kernel NULL pointer dereference at virtual address 0000000000000008<br />Mem abort info:<br /> ESR = 0x0000000096000004<br /> EC = 0x25: DABT (current EL), IL = 32 bits<br /> SET = 0, FnV = 0<br /> EA = 0, S1PTW = 0<br /> FSC = 0x04: level 0 translation fault<br /> Data abort info:<br /> ISV = 0, ISS = 0x00000004, ISS2 = 0x00000000<br /> CM = 0, WnR = 0, TnD = 0, TagAccess = 0<br /> GCS = 0, Overlay = 0, DirtyBit = 0, Xs = 0<br /> user pgtable: 4k pages, 48-bit VAs, pgdp=00000001076e5000<br /> [0000000000000008] pgd=0000000000000000, p4d=0000000000000000<br /> Internal error: Oops: 0000000096000004 [#1] PREEMPT SMP<br /> Modules linked in: scmi_perf_domain(-) scmi_module scmi_core<br /> CPU: 0 PID: 231 Comm: rmmod Not tainted 6.7.0-00084-gb4b1f27d3b83-dirty #15<br /> Hardware name: linux,dummy-virt (DT)<br /> pstate: 61400005 (nZCv daif +PAN -UAO -TCO +DIT -SSBS BTYPE=--)<br /> pc : scmi_perf_domain_remove+0x28/0x70 [scmi_perf_domain]<br /> lr : scmi_perf_domain_remove+0x28/0x70 [scmi_perf_domain]<br /> sp : ffff80008393bc10<br /> x29: ffff80008393bc10 x28: ffff0000875a8000 x27: 0000000000000000<br /> x26: 0000000000000000 x25: 0000000000000000 x24: 0000000000000000<br /> x23: ffff00008030c090 x22: ffff00008032d490 x21: ffff80007b287050<br /> x20: 0000000000000000 x19: ffff00008032d410 x18: 0000000000000000<br /> x17: 0000000000000000 x16: 0000000000000000 x15: 0000000000000000<br /> x14: 8ba0696d05013a2f x13: 0000000000000000 x12: 0000000000000002<br /> x11: 0101010101010101 x10: ffff00008510cff8 x9 : ffff800080a6797c<br /> x8 : 0101010101010101 x7 : 7f7f7f7f7f7f7f7f x6 : fefefeff6364626d<br /> x5 : 8080808000000000 x4 : 0000000000000020 x3 : 00000000553a3dc1<br /> x2 : ffff0000875a8000 x1 : ffff0000875a8000 x0 : ffff800082ffa048<br /> Call trace:<br /> scmi_perf_domain_remove+0x28/0x70 [scmi_perf_domain]<br /> scmi_dev_remove+0x28/0x40 [scmi_core]<br /> device_remove+0x54/0x90<br /> device_release_driver_internal+0x1dc/0x240<br /> driver_detach+0x58/0xa8<br /> bus_remove_driver+0x78/0x108<br /> driver_unregister+0x38/0x70<br /> scmi_driver_unregister+0x28/0x180 [scmi_core]<br /> scmi_perf_domain_driver_exit+0x18/0xb78 [scmi_perf_domain]<br /> __arm64_sys_delete_module+0x1a8/0x2c0<br /> invoke_syscall+0x50/0x128<br /> el0_svc_common.constprop.0+0x48/0xf0<br /> do_el0_svc+0x24/0x38<br /> el0_svc+0x34/0xb8<br /> el0t_64_sync_handler+0x100/0x130<br /> el0t_64_sync+0x190/0x198<br /> Code: a90153f3 f9403c14 f9414800 955f8a05 (b9400a80)<br /> ---[ end trace 0000000000000000 ]---<br /><br />Cc: Sudeep Holla <sudeep.holla@arm.com><br />Cc: Ulf Hansson <ulf.hansson@linaro.org><br />Fixes: 2af23ceb8624 ("pmdomain: arm: Add the SCMI performance domain")<br />Signed-off-by: Cristian Marussi <cristian.marussi@arm.com><br />---<br />I suppose the probe does NOT bail out with an error because this DT config has<br />to be supported, right ?<br />---<br /> drivers/pmdomain/arm/scmi_perf_domain.c | 3 +++<br /> 1 file changed, 3 insertions(+)<br /><br />diff --git a/drivers/pmdomain/arm/scmi_perf_domain.c b/drivers/pmdomain/arm/scmi_perf_domain.c<br />index 709bbc448fad..d7ef46ccd9b8 100644<br />--- a/drivers/pmdomain/arm/scmi_perf_domain.c<br />+++ b/drivers/pmdomain/arm/scmi_perf_domain.c<br />@@ -159,6 +159,9 @@ static void scmi_perf_domain_remove(struct scmi_device *sdev)<br /> struct genpd_onecell_data *scmi_pd_data = dev_get_drvdata(dev);<br /> int i;<br /> <br />+ if (!scmi_pd_data)<br />+ return;<br />+<br /> of_genpd_del_provider(dev->of_node);<br /> <br /> for (i = 0; i < scmi_pd_data->num_domains; i++)<br />-- <br />2.43.0<br /><br /></pre></td><td width="32" rowspan="2" class="c" valign="top"><img src="/images/icornerr.gif" width="32" height="32" alt="\" /></td></tr><tr><td align="right" valign="bottom"> 聽 </td></tr><tr><td align="right" valign="bottom">聽</td><td class="c" valign="bottom" style="padding-bottom: 0px"><img src="/images/bcornerl.gif" width="32" height="32" alt="\" /></td><td class="c">聽</td><td class="c" valign="bottom" style="padding-bottom: 0px"><img src="/images/bcornerr.gif" width="32" height="32" alt="/" /></td></tr><tr><td align="right" valign="top" colspan="2"> 聽 </td><td class="lm">Last update: 2024-05-27 14:34 聽聽 [from the cache]<br />漏2003-2020 <a href="http://blog.jasper.es/"><span itemprop="editor">Jasper Spaans</span></a>|hosted at <a 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