| Message ID | 20211108082429.15080-1-yong.wu@mediatek.com (mailing list archive) |
|---|---|
| State | New, archived |
| Headers | show |
| Series | [v2] memory: mtk-smi: Fix a null dereference for the ostd | expand |
Il 08/11/21 09:24, Yong Wu ha scritto: > We add the ostd setting for mt8195. It introduces a KE for the > previous SoC which doesn't have ostd setting. This is the log: > > Unable to handle kernel NULL pointer dereference at virtual address > 0000000000000080 > ... > pc : mtk_smi_larb_config_port_gen2_general+0x64/0x130 > lr : mtk_smi_larb_resume+0x54/0x98 > ... > Call trace: > mtk_smi_larb_config_port_gen2_general+0x64/0x130 > pm_generic_runtime_resume+0x2c/0x48 > __genpd_runtime_resume+0x30/0xa8 > genpd_runtime_resume+0x94/0x2c8 > __rpm_callback+0x44/0x150 > rpm_callback+0x6c/0x78 > rpm_resume+0x310/0x558 > __pm_runtime_resume+0x3c/0x88 > > In the code: larbostd = larb->larb_gen->ostd[larb->larbid], > if "larb->larb_gen->ostd" is null, the "larbostd" is the offset(e.g. > 0x80 above), it's also a valid value, then accessing "larbostd[i]" in the > "for" loop will cause the KE above. To avoid this issue, initialize > "larbostd" to NULL when the SoC doesn't have ostd setting. > > Signed-off-by: Yong Wu <yong.wu@mediatek.com> > --- > change note: Reword the commit message to show why it KE. and update the > solution via initializing "larbostd" is NULL explicitly in the non-ostd > case. > --- > drivers/memory/mtk-smi.c | 2 +- > 1 file changed, 1 insertion(+), 1 deletion(-) > This commit needs a Fixes tag. Please add the proper one.
Hi AngeloGioacchino, Thanks very much for your help review. On Thu, 2021-11-11 at 14:41 +0100, AngeloGioacchino Del Regno wrote: > Il 08/11/21 09:24, Yong Wu ha scritto: > > We add the ostd setting for mt8195. It introduces a KE for the > > previous SoC which doesn't have ostd setting. This is the log: > > > > Unable to handle kernel NULL pointer dereference at virtual address > > 0000000000000080 > > ... > > pc : mtk_smi_larb_config_port_gen2_general+0x64/0x130 > > lr : mtk_smi_larb_resume+0x54/0x98 > > ... > > Call trace: > > mtk_smi_larb_config_port_gen2_general+0x64/0x130 > > pm_generic_runtime_resume+0x2c/0x48 > > __genpd_runtime_resume+0x30/0xa8 > > genpd_runtime_resume+0x94/0x2c8 > > __rpm_callback+0x44/0x150 > > rpm_callback+0x6c/0x78 > > rpm_resume+0x310/0x558 > > __pm_runtime_resume+0x3c/0x88 > > > > In the code: larbostd = larb->larb_gen->ostd[larb->larbid], > > if "larb->larb_gen->ostd" is null, the "larbostd" is the > > offset(e.g. > > 0x80 above), it's also a valid value, then accessing "larbostd[i]" > > in the > > "for" loop will cause the KE above. To avoid this issue, initialize > > "larbostd" to NULL when the SoC doesn't have ostd setting. > > > > Signed-off-by: Yong Wu <yong.wu@mediatek.com> > > --- > > change note: Reword the commit message to show why it KE. and > > update the > > solution via initializing "larbostd" is NULL explicitly in the non- > > ostd > > case. > > --- > > drivers/memory/mtk-smi.c | 2 +- > > 1 file changed, 1 insertion(+), 1 deletion(-) > > > > This commit needs a Fixes tag. Please add the proper one. This should fix this one: fe6dd2a4017d ("memory: mtk-smi: mt8195: Add initial setting for smi- larb") But the commit id comes from linux-next. I'm not sure if the sha-id will be changed again when enter mainline. so I didn't add it.
On Mon, 8 Nov 2021 16:24:29 +0800, Yong Wu wrote: > We add the ostd setting for mt8195. It introduces a KE for the > previous SoC which doesn't have ostd setting. This is the log: > > Unable to handle kernel NULL pointer dereference at virtual address > 0000000000000080 > ... > pc : mtk_smi_larb_config_port_gen2_general+0x64/0x130 > lr : mtk_smi_larb_resume+0x54/0x98 > ... > Call trace: > mtk_smi_larb_config_port_gen2_general+0x64/0x130 > pm_generic_runtime_resume+0x2c/0x48 > __genpd_runtime_resume+0x30/0xa8 > genpd_runtime_resume+0x94/0x2c8 > __rpm_callback+0x44/0x150 > rpm_callback+0x6c/0x78 > rpm_resume+0x310/0x558 > __pm_runtime_resume+0x3c/0x88 > > [...] Applied, thanks! [1/1] memory: mtk-smi: Fix a null dereference for the ostd commit: 8c5ba21c16bd7f8e23b8740dead6eaf164b8caa0 Best regards,
diff --git a/drivers/memory/mtk-smi.c b/drivers/memory/mtk-smi.c index b883dcc0bbfa..e201e5976f34 100644 --- a/drivers/memory/mtk-smi.c +++ b/drivers/memory/mtk-smi.c @@ -241,7 +241,7 @@ static void mtk_smi_larb_config_port_gen2_general(struct device *dev) { struct mtk_smi_larb *larb = dev_get_drvdata(dev); u32 reg, flags_general = larb->larb_gen->flags_general; - const u8 *larbostd = larb->larb_gen->ostd[larb->larbid]; + const u8 *larbostd = larb->larb_gen->ostd ? larb->larb_gen->ostd[larb->larbid] : NULL; int i; if (BIT(larb->larbid) & larb->larb_gen->larb_direct_to_common_mask)
We add the ostd setting for mt8195. It introduces a KE for the previous SoC which doesn't have ostd setting. This is the log: Unable to handle kernel NULL pointer dereference at virtual address 0000000000000080 ... pc : mtk_smi_larb_config_port_gen2_general+0x64/0x130 lr : mtk_smi_larb_resume+0x54/0x98 ... Call trace: mtk_smi_larb_config_port_gen2_general+0x64/0x130 pm_generic_runtime_resume+0x2c/0x48 __genpd_runtime_resume+0x30/0xa8 genpd_runtime_resume+0x94/0x2c8 __rpm_callback+0x44/0x150 rpm_callback+0x6c/0x78 rpm_resume+0x310/0x558 __pm_runtime_resume+0x3c/0x88 In the code: larbostd = larb->larb_gen->ostd[larb->larbid], if "larb->larb_gen->ostd" is null, the "larbostd" is the offset(e.g. 0x80 above), it's also a valid value, then accessing "larbostd[i]" in the "for" loop will cause the KE above. To avoid this issue, initialize "larbostd" to NULL when the SoC doesn't have ostd setting. Signed-off-by: Yong Wu <yong.wu@mediatek.com> --- change note: Reword the commit message to show why it KE. and update the solution via initializing "larbostd" is NULL explicitly in the non-ostd case. --- drivers/memory/mtk-smi.c | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-)