[Kernel-packages] [Bug 1800566] Re: Make reset_devices parameter default for kdump and decouple kdump systemd service from the KDUMP_CMDLINE_APPEND
** Changed in: makedumpfile (Ubuntu Disco) Status: Won't Fix => In Progress -- You received this bug notification because you are a member of Kernel Packages, which is subscribed to makedumpfile in Ubuntu. https://bugs.launchpad.net/bugs/1800566 Title: Make reset_devices parameter default for kdump and decouple kdump systemd service from the KDUMP_CMDLINE_APPEND Status in makedumpfile package in Ubuntu: In Progress Status in makedumpfile source package in Trusty: Won't Fix Status in makedumpfile source package in Xenial: In Progress Status in makedumpfile source package in Bionic: In Progress Status in makedumpfile source package in Cosmic: Won't Fix Status in makedumpfile source package in Disco: In Progress Status in makedumpfile source package in Eoan: In Progress Status in makedumpfile source package in Focal: In Progress Bug description: [Impact] * Kdump does not configure by default the crash kernel to perform a device reset by default, by passing the "reset_devices" parameter. Also, the systemd service "kdump-tools-dump" is tightly-coupled with KDUMP_CMDLINE_APPEND and it shouldn't, to prevent user confusion. * Kernel has the "reset_devices" parameter that drivers can opt-in, and perform special activity in case this parameter is parsed from command-line. For example, in kdump kernels it hints the drivers that they are booting from a non-healthy condition and needs to issue some form of reset to the adapter, like clearing DMA mapping in their firmware for example. Users currently (kernel v5.2) are: aacraid, hpsa, ipr, megaraid_sas, mpt3sas, smartpqi, xenbus. This should be enabled by default in the kdump config file to be added in the kdump kernel command-line for all versions. * The systemd service"kdump-tools-dump" is responsible for triggering the execution of the makedumpfile tool ultimately. Kdump from Xenial+ releases rely on systemd as their init system, so this service is the way to trigger the kdump mechanism. Currently it is configured as any other parameter in KDUMP_CMDLINE_APPEND, meaning if user decides to change the line they need to remember adding the systemd service back. It's not really a parameter that should be easily manipulated in kdump line, since there's no use for it except to instruct systemd to load kdump; the only reasonable case for removing it is to debug kdump itself. [Test Case] 1) Deploy a Disco VM e.g. with uvt-kvm 2) Install the kdump-tools package 3) Run `kdump-config test`and check for the 'reset_devices' parameter: $ kdump-config test ... kexec command to be used: /sbin/kexec -p --command-line="BOOT_IMAGE=/boot/vmlinuz-4.15.0-45-generic root=LABEL=cloudimg-rootfs ro console=tty1 console=ttyS0 nr_cpus=1 systemd.unit=kdump-tools.service irqpoll nousb ata_piix.prefer_ms_hyperv=0" /var/lib/kdump/vmlinuz Also, by changing the KDUMP_CMDLINE_APPEND we can see "systemd.unit =kdump-tools.service" to be removed. [Regression Potential] The regression potential is low, since it doesn't need any changes in makedumpfile code and we're only adding a parameter on the crash kernel command-line. The risks are related with bad behavior with the kernel when using "reset_devices", like if the driver has bugs in this path. It's considered safer to have the option (and this way prevent problems for booting a unhealthy kernel with potential stuck DMAs in the devices) than not having it. Regarding the other change, about the systemd service, it'll only affect users the are debugging kdump itself and it has no known regression potential. To manage notifications about this bug go to: https://bugs.launchpad.net/ubuntu/+source/makedumpfile/+bug/1800566/+subscriptions -- Mailing list: https://launchpad.net/~kernel-packages Post to : kernel-packages@lists.launchpad.net Unsubscribe : https://launchpad.net/~kernel-packages More help : https://help.launchpad.net/ListHelp
[Kernel-packages] [Bug 1800566] Re: Make reset_devices parameter default for kdump and decouple kdump systemd service from the KDUMP_CMDLINE_APPEND
** Changed in: makedumpfile (Ubuntu Disco) Status: Confirmed => Won't Fix ** Changed in: makedumpfile (Ubuntu Focal) Status: Confirmed => In Progress ** Changed in: makedumpfile (Ubuntu Eoan) Status: Confirmed => In Progress ** Changed in: makedumpfile (Ubuntu Bionic) Status: Confirmed => In Progress ** Changed in: makedumpfile (Ubuntu Xenial) Status: Confirmed => In Progress -- You received this bug notification because you are a member of Kernel Packages, which is subscribed to makedumpfile in Ubuntu. https://bugs.launchpad.net/bugs/1800566 Title: Make reset_devices parameter default for kdump and decouple kdump systemd service from the KDUMP_CMDLINE_APPEND Status in makedumpfile package in Ubuntu: In Progress Status in makedumpfile source package in Trusty: Won't Fix Status in makedumpfile source package in Xenial: In Progress Status in makedumpfile source package in Bionic: In Progress Status in makedumpfile source package in Cosmic: Won't Fix Status in makedumpfile source package in Disco: Won't Fix Status in makedumpfile source package in Eoan: In Progress Status in makedumpfile source package in Focal: In Progress Bug description: [Impact] * Kdump does not configure by default the crash kernel to perform a device reset by default, by passing the "reset_devices" parameter. Also, the systemd service "kdump-tools-dump" is tightly-coupled with KDUMP_CMDLINE_APPEND and it shouldn't, to prevent user confusion. * Kernel has the "reset_devices" parameter that drivers can opt-in, and perform special activity in case this parameter is parsed from command-line. For example, in kdump kernels it hints the drivers that they are booting from a non-healthy condition and needs to issue some form of reset to the adapter, like clearing DMA mapping in their firmware for example. Users currently (kernel v5.2) are: aacraid, hpsa, ipr, megaraid_sas, mpt3sas, smartpqi, xenbus. This should be enabled by default in the kdump config file to be added in the kdump kernel command-line for all versions. * The systemd service"kdump-tools-dump" is responsible for triggering the execution of the makedumpfile tool ultimately. Kdump from Xenial+ releases rely on systemd as their init system, so this service is the way to trigger the kdump mechanism. Currently it is configured as any other parameter in KDUMP_CMDLINE_APPEND, meaning if user decides to change the line they need to remember adding the systemd service back. It's not really a parameter that should be easily manipulated in kdump line, since there's no use for it except to instruct systemd to load kdump; the only reasonable case for removing it is to debug kdump itself. [Test Case] 1) Deploy a Disco VM e.g. with uvt-kvm 2) Install the kdump-tools package 3) Run `kdump-config test`and check for the 'reset_devices' parameter: $ kdump-config test ... kexec command to be used: /sbin/kexec -p --command-line="BOOT_IMAGE=/boot/vmlinuz-4.15.0-45-generic root=LABEL=cloudimg-rootfs ro console=tty1 console=ttyS0 nr_cpus=1 systemd.unit=kdump-tools.service irqpoll nousb ata_piix.prefer_ms_hyperv=0" /var/lib/kdump/vmlinuz Also, by changing the KDUMP_CMDLINE_APPEND we can see "systemd.unit =kdump-tools.service" to be removed. [Regression Potential] The regression potential is low, since it doesn't need any changes in makedumpfile code and we're only adding a parameter on the crash kernel command-line. The risks are related with bad behavior with the kernel when using "reset_devices", like if the driver has bugs in this path. It's considered safer to have the option (and this way prevent problems for booting a unhealthy kernel with potential stuck DMAs in the devices) than not having it. Regarding the other change, about the systemd service, it'll only affect users the are debugging kdump itself and it has no known regression potential. To manage notifications about this bug go to: https://bugs.launchpad.net/ubuntu/+source/makedumpfile/+bug/1800566/+subscriptions -- Mailing list: https://launchpad.net/~kernel-packages Post to : kernel-packages@lists.launchpad.net Unsubscribe : https://launchpad.net/~kernel-packages More help : https://help.launchpad.net/ListHelp
[Kernel-packages] [Bug 1800566] Re: Make reset_devices parameter default for kdump and decouple kdump systemd service from the KDUMP_CMDLINE_APPEND
** Changed in: makedumpfile (Ubuntu Eoan) Status: In Progress => Confirmed ** Changed in: makedumpfile (Ubuntu Focal) Status: In Progress => Confirmed -- You received this bug notification because you are a member of Kernel Packages, which is subscribed to makedumpfile in Ubuntu. https://bugs.launchpad.net/bugs/1800566 Title: Make reset_devices parameter default for kdump and decouple kdump systemd service from the KDUMP_CMDLINE_APPEND Status in makedumpfile package in Ubuntu: Confirmed Status in makedumpfile source package in Trusty: Won't Fix Status in makedumpfile source package in Xenial: Confirmed Status in makedumpfile source package in Bionic: Confirmed Status in makedumpfile source package in Cosmic: Won't Fix Status in makedumpfile source package in Disco: Confirmed Status in makedumpfile source package in Eoan: Confirmed Status in makedumpfile source package in Focal: Confirmed Bug description: [Impact] * Kdump does not configure by default the crash kernel to perform a device reset by default, by passing the "reset_devices" parameter. Also, the systemd service "kdump-tools-dump" is tightly-coupled with KDUMP_CMDLINE_APPEND and it shouldn't, to prevent user confusion. * Kernel has the "reset_devices" parameter that drivers can opt-in, and perform special activity in case this parameter is parsed from command-line. For example, in kdump kernels it hints the drivers that they are booting from a non-healthy condition and needs to issue some form of reset to the adapter, like clearing DMA mapping in their firmware for example. Users currently (kernel v5.2) are: aacraid, hpsa, ipr, megaraid_sas, mpt3sas, smartpqi, xenbus. This should be enabled by default in the kdump config file to be added in the kdump kernel command-line for all versions. * The systemd service"kdump-tools-dump" is responsible for triggering the execution of the makedumpfile tool ultimately. Kdump from Xenial+ releases rely on systemd as their init system, so this service is the way to trigger the kdump mechanism. Currently it is configured as any other parameter in KDUMP_CMDLINE_APPEND, meaning if user decides to change the line they need to remember adding the systemd service back. It's not really a parameter that should be easily manipulated in kdump line, since there's no use for it except to instruct systemd to load kdump; the only reasonable case for removing it is to debug kdump itself. [Test Case] 1) Deploy a Disco VM e.g. with uvt-kvm 2) Install the kdump-tools package 3) Run `kdump-config test`and check for the 'reset_devices' parameter: $ kdump-config test ... kexec command to be used: /sbin/kexec -p --command-line="BOOT_IMAGE=/boot/vmlinuz-4.15.0-45-generic root=LABEL=cloudimg-rootfs ro console=tty1 console=ttyS0 nr_cpus=1 systemd.unit=kdump-tools.service irqpoll nousb ata_piix.prefer_ms_hyperv=0" /var/lib/kdump/vmlinuz Also, by changing the KDUMP_CMDLINE_APPEND we can see "systemd.unit =kdump-tools.service" to be removed. [Regression Potential] The regression potential is low, since it doesn't need any changes in makedumpfile code and we're only adding a parameter on the crash kernel command-line. The risks are related with bad behavior with the kernel when using "reset_devices", like if the driver has bugs in this path. It's considered safer to have the option (and this way prevent problems for booting a unhealthy kernel with potential stuck DMAs in the devices) than not having it. Regarding the other change, about the systemd service, it'll only affect users the are debugging kdump itself and it has no known regression potential. To manage notifications about this bug go to: https://bugs.launchpad.net/ubuntu/+source/makedumpfile/+bug/1800566/+subscriptions -- Mailing list: https://launchpad.net/~kernel-packages Post to : kernel-packages@lists.launchpad.net Unsubscribe : https://launchpad.net/~kernel-packages More help : https://help.launchpad.net/ListHelp
[Kernel-packages] [Bug 1800566] Re: Make reset_devices parameter default for kdump and decouple kdump systemd service from the KDUMP_CMDLINE_APPEND
** Also affects: makedumpfile (Ubuntu Focal) Importance: High Assignee: Guilherme G. Piccoli (gpiccoli) Status: In Progress -- You received this bug notification because you are a member of Kernel Packages, which is subscribed to makedumpfile in Ubuntu. https://bugs.launchpad.net/bugs/1800566 Title: Make reset_devices parameter default for kdump and decouple kdump systemd service from the KDUMP_CMDLINE_APPEND Status in makedumpfile package in Ubuntu: In Progress Status in makedumpfile source package in Trusty: Won't Fix Status in makedumpfile source package in Xenial: Confirmed Status in makedumpfile source package in Bionic: Confirmed Status in makedumpfile source package in Cosmic: Won't Fix Status in makedumpfile source package in Disco: Confirmed Status in makedumpfile source package in Eoan: In Progress Status in makedumpfile source package in Focal: In Progress Bug description: [Impact] * Kdump does not configure by default the crash kernel to perform a device reset by default, by passing the "reset_devices" parameter. Also, the systemd service "kdump-tools-dump" is tightly-coupled with KDUMP_CMDLINE_APPEND and it shouldn't, to prevent user confusion. * Kernel has the "reset_devices" parameter that drivers can opt-in, and perform special activity in case this parameter is parsed from command-line. For example, in kdump kernels it hints the drivers that they are booting from a non-healthy condition and needs to issue some form of reset to the adapter, like clearing DMA mapping in their firmware for example. Users currently (kernel v5.2) are: aacraid, hpsa, ipr, megaraid_sas, mpt3sas, smartpqi, xenbus. This should be enabled by default in the kdump config file to be added in the kdump kernel command-line for all versions. * The systemd service"kdump-tools-dump" is responsible for triggering the execution of the makedumpfile tool ultimately. Kdump from Xenial+ releases rely on systemd as their init system, so this service is the way to trigger the kdump mechanism. Currently it is configured as any other parameter in KDUMP_CMDLINE_APPEND, meaning if user decides to change the line they need to remember adding the systemd service back. It's not really a parameter that should be easily manipulated in kdump line, since there's no use for it except to instruct systemd to load kdump; the only reasonable case for removing it is to debug kdump itself. [Test Case] 1) Deploy a Disco VM e.g. with uvt-kvm 2) Install the kdump-tools package 3) Run `kdump-config test`and check for the 'reset_devices' parameter: $ kdump-config test ... kexec command to be used: /sbin/kexec -p --command-line="BOOT_IMAGE=/boot/vmlinuz-4.15.0-45-generic root=LABEL=cloudimg-rootfs ro console=tty1 console=ttyS0 nr_cpus=1 systemd.unit=kdump-tools.service irqpoll nousb ata_piix.prefer_ms_hyperv=0" /var/lib/kdump/vmlinuz Also, by changing the KDUMP_CMDLINE_APPEND we can see "systemd.unit =kdump-tools.service" to be removed. [Regression Potential] The regression potential is low, since it doesn't need any changes in makedumpfile code and we're only adding a parameter on the crash kernel command-line. The risks are related with bad behavior with the kernel when using "reset_devices", like if the driver has bugs in this path. It's considered safer to have the option (and this way prevent problems for booting a unhealthy kernel with potential stuck DMAs in the devices) than not having it. Regarding the other change, about the systemd service, it'll only affect users the are debugging kdump itself and it has no known regression potential. To manage notifications about this bug go to: https://bugs.launchpad.net/ubuntu/+source/makedumpfile/+bug/1800566/+subscriptions -- Mailing list: https://launchpad.net/~kernel-packages Post to : kernel-packages@lists.launchpad.net Unsubscribe : https://launchpad.net/~kernel-packages More help : https://help.launchpad.net/ListHelp
[Kernel-packages] [Bug 1800566] Re: Make reset_devices parameter default for kdump and decouple kdump systemd service from the KDUMP_CMDLINE_APPEND
** Changed in: makedumpfile (Ubuntu Cosmic) Status: Confirmed => Won't Fix -- You received this bug notification because you are a member of Kernel Packages, which is subscribed to makedumpfile in Ubuntu. https://bugs.launchpad.net/bugs/1800566 Title: Make reset_devices parameter default for kdump and decouple kdump systemd service from the KDUMP_CMDLINE_APPEND Status in makedumpfile package in Ubuntu: In Progress Status in makedumpfile source package in Trusty: Won't Fix Status in makedumpfile source package in Xenial: Confirmed Status in makedumpfile source package in Bionic: Confirmed Status in makedumpfile source package in Cosmic: Won't Fix Status in makedumpfile source package in Disco: Confirmed Status in makedumpfile source package in Eoan: In Progress Bug description: [Impact] * Kdump does not configure by default the crash kernel to perform a device reset by default, by passing the "reset_devices" parameter. Also, the systemd service "kdump-tools-dump" is tightly-coupled with KDUMP_CMDLINE_APPEND and it shouldn't, to prevent user confusion. * Kernel has the "reset_devices" parameter that drivers can opt-in, and perform special activity in case this parameter is parsed from command-line. For example, in kdump kernels it hints the drivers that they are booting from a non-healthy condition and needs to issue some form of reset to the adapter, like clearing DMA mapping in their firmware for example. Users currently (kernel v5.2) are: aacraid, hpsa, ipr, megaraid_sas, mpt3sas, smartpqi, xenbus. This should be enabled by default in the kdump config file to be added in the kdump kernel command-line for all versions. * The systemd service"kdump-tools-dump" is responsible for triggering the execution of the makedumpfile tool ultimately. Kdump from Xenial+ releases rely on systemd as their init system, so this service is the way to trigger the kdump mechanism. Currently it is configured as any other parameter in KDUMP_CMDLINE_APPEND, meaning if user decides to change the line they need to remember adding the systemd service back. It's not really a parameter that should be easily manipulated in kdump line, since there's no use for it except to instruct systemd to load kdump; the only reasonable case for removing it is to debug kdump itself. [Test Case] 1) Deploy a Disco VM e.g. with uvt-kvm 2) Install the kdump-tools package 3) Run `kdump-config test`and check for the 'reset_devices' parameter: $ kdump-config test ... kexec command to be used: /sbin/kexec -p --command-line="BOOT_IMAGE=/boot/vmlinuz-4.15.0-45-generic root=LABEL=cloudimg-rootfs ro console=tty1 console=ttyS0 nr_cpus=1 systemd.unit=kdump-tools.service irqpoll nousb ata_piix.prefer_ms_hyperv=0" /var/lib/kdump/vmlinuz Also, by changing the KDUMP_CMDLINE_APPEND we can see "systemd.unit =kdump-tools.service" to be removed. [Regression Potential] The regression potential is low, since it doesn't need any changes in makedumpfile code and we're only adding a parameter on the crash kernel command-line. The risks are related with bad behavior with the kernel when using "reset_devices", like if the driver has bugs in this path. It's considered safer to have the option (and this way prevent problems for booting a unhealthy kernel with potential stuck DMAs in the devices) than not having it. Regarding the other change, about the systemd service, it'll only affect users the are debugging kdump itself and it has no known regression potential. To manage notifications about this bug go to: https://bugs.launchpad.net/ubuntu/+source/makedumpfile/+bug/1800566/+subscriptions -- Mailing list: https://launchpad.net/~kernel-packages Post to : kernel-packages@lists.launchpad.net Unsubscribe : https://launchpad.net/~kernel-packages More help : https://help.launchpad.net/ListHelp
[Kernel-packages] [Bug 1800566] Re: Make reset_devices parameter default for kdump and decouple kdump systemd service from the KDUMP_CMDLINE_APPEND
The attachment "lp1800566_eoan.debdiff" seems to be a debdiff. The ubuntu-sponsors team has been subscribed to the bug report so that they can review and hopefully sponsor the debdiff. If the attachment isn't a patch, please remove the "patch" flag from the attachment, remove the "patch" tag, and if you are member of the ~ubuntu-sponsors, unsubscribe the team. [This is an automated message performed by a Launchpad user owned by ~brian-murray, for any issue please contact him.] ** Tags added: patch -- You received this bug notification because you are a member of Kernel Packages, which is subscribed to makedumpfile in Ubuntu. https://bugs.launchpad.net/bugs/1800566 Title: Make reset_devices parameter default for kdump and decouple kdump systemd service from the KDUMP_CMDLINE_APPEND Status in makedumpfile package in Ubuntu: In Progress Status in makedumpfile source package in Trusty: Won't Fix Status in makedumpfile source package in Xenial: Confirmed Status in makedumpfile source package in Bionic: Confirmed Status in makedumpfile source package in Cosmic: Confirmed Status in makedumpfile source package in Disco: Confirmed Status in makedumpfile source package in Eoan: In Progress Bug description: [Impact] * Kdump does not configure by default the crash kernel to perform a device reset by default, by passing the "reset_devices" parameter. Also, the systemd service "kdump-tools-dump" is tightly-coupled with KDUMP_CMDLINE_APPEND and it shouldn't, to prevent user confusion. * Kernel has the "reset_devices" parameter that drivers can opt-in, and perform special activity in case this parameter is parsed from command-line. For example, in kdump kernels it hints the drivers that they are booting from a non-healthy condition and needs to issue some form of reset to the adapter, like clearing DMA mapping in their firmware for example. Users currently (kernel v5.2) are: aacraid, hpsa, ipr, megaraid_sas, mpt3sas, smartpqi, xenbus. This should be enabled by default in the kdump config file to be added in the kdump kernel command-line for all versions. * The systemd service"kdump-tools-dump" is responsible for triggering the execution of the makedumpfile tool ultimately. Kdump from Xenial+ releases rely on systemd as their init system, so this service is the way to trigger the kdump mechanism. Currently it is configured as any other parameter in KDUMP_CMDLINE_APPEND, meaning if user decides to change the line they need to remember adding the systemd service back. It's not really a parameter that should be easily manipulated in kdump line, since there's no use for it except to instruct systemd to load kdump; the only reasonable case for removing it is to debug kdump itself. [Test Case] 1) Deploy a Disco VM e.g. with uvt-kvm 2) Install the kdump-tools package 3) Run `kdump-config test`and check for the 'reset_devices' parameter: $ kdump-config test ... kexec command to be used: /sbin/kexec -p --command-line="BOOT_IMAGE=/boot/vmlinuz-4.15.0-45-generic root=LABEL=cloudimg-rootfs ro console=tty1 console=ttyS0 nr_cpus=1 systemd.unit=kdump-tools.service irqpoll nousb ata_piix.prefer_ms_hyperv=0" /var/lib/kdump/vmlinuz Also, by changing the KDUMP_CMDLINE_APPEND we can see "systemd.unit =kdump-tools.service" to be removed. [Regression Potential] The regression potential is low, since it doesn't need any changes in makedumpfile code and we're only adding a parameter on the crash kernel command-line. The risks are related with bad behavior with the kernel when using "reset_devices", like if the driver has bugs in this path. It's considered safer to have the option (and this way prevent problems for booting a unhealthy kernel with potential stuck DMAs in the devices) than not having it. Regarding the other change, about the systemd service, it'll only affect users the are debugging kdump itself and it has no known regression potential. To manage notifications about this bug go to: https://bugs.launchpad.net/ubuntu/+source/makedumpfile/+bug/1800566/+subscriptions -- Mailing list: https://launchpad.net/~kernel-packages Post to : kernel-packages@lists.launchpad.net Unsubscribe : https://launchpad.net/~kernel-packages More help : https://help.launchpad.net/ListHelp
[Kernel-packages] [Bug 1800566] Re: Make reset_devices parameter default for kdump and decouple kdump systemd service from the KDUMP_CMDLINE_APPEND
This is the debdiff with this LP's proposed modifications. I'd like to specially thanks Cascardo and Heitor for the discussions and joint work in this issue. ** Changed in: makedumpfile (Ubuntu Eoan) Status: Confirmed => In Progress ** Patch added: "lp1800566_eoan.debdiff" https://bugs.launchpad.net/ubuntu/+source/makedumpfile/+bug/1800566/+attachment/5275118/+files/lp1800566_eoan.debdiff -- You received this bug notification because you are a member of Kernel Packages, which is subscribed to makedumpfile in Ubuntu. https://bugs.launchpad.net/bugs/1800566 Title: Make reset_devices parameter default for kdump and decouple kdump systemd service from the KDUMP_CMDLINE_APPEND Status in makedumpfile package in Ubuntu: In Progress Status in makedumpfile source package in Trusty: Won't Fix Status in makedumpfile source package in Xenial: Confirmed Status in makedumpfile source package in Bionic: Confirmed Status in makedumpfile source package in Cosmic: Confirmed Status in makedumpfile source package in Disco: Confirmed Status in makedumpfile source package in Eoan: In Progress Bug description: [Impact] * Kdump does not configure by default the crash kernel to perform a device reset by default, by passing the "reset_devices" parameter. Also, the systemd service "kdump-tools-dump" is tightly-coupled with KDUMP_CMDLINE_APPEND and it shouldn't, to prevent user confusion. * Kernel has the "reset_devices" parameter that drivers can opt-in, and perform special activity in case this parameter is parsed from command-line. For example, in kdump kernels it hints the drivers that they are booting from a non-healthy condition and needs to issue some form of reset to the adapter, like clearing DMA mapping in their firmware for example. Users currently (kernel v5.2) are: aacraid, hpsa, ipr, megaraid_sas, mpt3sas, smartpqi, xenbus. This should be enabled by default in the kdump config file to be added in the kdump kernel command-line for all versions. * The systemd service"kdump-tools-dump" is responsible for triggering the execution of the makedumpfile tool ultimately. Kdump from Xenial+ releases rely on systemd as their init system, so this service is the way to trigger the kdump mechanism. Currently it is configured as any other parameter in KDUMP_CMDLINE_APPEND, meaning if user decides to change the line they need to remember adding the systemd service back. It's not really a parameter that should be easily manipulated in kdump line, since there's no use for it except to instruct systemd to load kdump; the only reasonable case for removing it is to debug kdump itself. [Test Case] 1) Deploy a Disco VM e.g. with uvt-kvm 2) Install the kdump-tools package 3) Run `kdump-config test`and check for the 'reset_devices' parameter: $ kdump-config test ... kexec command to be used: /sbin/kexec -p --command-line="BOOT_IMAGE=/boot/vmlinuz-4.15.0-45-generic root=LABEL=cloudimg-rootfs ro console=tty1 console=ttyS0 nr_cpus=1 systemd.unit=kdump-tools.service irqpoll nousb ata_piix.prefer_ms_hyperv=0" /var/lib/kdump/vmlinuz Also, by changing the KDUMP_CMDLINE_APPEND we can see "systemd.unit =kdump-tools.service" to be removed. [Regression Potential] The regression potential is low, since it doesn't need any changes in makedumpfile code and we're only adding a parameter on the crash kernel command-line. The risks are related with bad behavior with the kernel when using "reset_devices", like if the driver has bugs in this path. It's considered safer to have the option (and this way prevent problems for booting a unhealthy kernel with potential stuck DMAs in the devices) than not having it. Regarding the other change, about the systemd service, it'll only affect users the are debugging kdump itself and it has no known regression potential. To manage notifications about this bug go to: https://bugs.launchpad.net/ubuntu/+source/makedumpfile/+bug/1800566/+subscriptions -- Mailing list: https://launchpad.net/~kernel-packages Post to : kernel-packages@lists.launchpad.net Unsubscribe : https://launchpad.net/~kernel-packages More help : https://help.launchpad.net/ListHelp
[Kernel-packages] [Bug 1800566] Re: Make reset_devices parameter default for kdump and decouple kdump systemd service from the KDUMP_CMDLINE_APPEND
** Description changed: [Impact] - Crash kernels do not advise some subsystems to perform a reset by default. - [Description] - Kernel has the "reset_devices" parameter that drivers can opt-in, and perform special activity in case this parameter is parsed from command-line. For example, in kdump kernels it hints the drivers that they (maybe) are booting from a non-healthy condition and needs to issue some reset to the adapter. Users currently (kernel v4.19) are: hpsa, ipr, megaraid_sas, mpt3sas, smartpqi, xenbus. + * Kdump does not configure by default the crash kernel to perform a + device reset by default, by passing the "reset_devices" parameter. Also, + the systemd service "kdump-tools-dump" is tightly-coupled with + KDUMP_CMDLINE_APPEND and it shouldn't, to prevent user confusion. + + * Kernel has the "reset_devices" parameter that drivers can opt-in, and + perform special activity in case this parameter is parsed from command- + line. For example, in kdump kernels it hints the drivers that they are + booting from a non-healthy condition and needs to issue some form of + reset to the adapter, like clearing DMA mapping in their firmware for + example. Users currently (kernel v5.2) are: aacraid, hpsa, ipr, + megaraid_sas, mpt3sas, smartpqi, xenbus. This should be enabled by default in the kdump config file to be added in the kdump kernel command-line for all versions. + * The systemd service"kdump-tools-dump" is responsible for triggering the execution of the makedumpfile tool ultimately. Kdump from Xenial+ releases rely on systemd as their init system, so this service is the way to trigger the kdump mechanism. Currently it is configured as any other parameter in KDUMP_CMDLINE_APPEND, meaning if user decides to change the line they need to remember adding the systemd service back. It's not really a parameter that should be easily manipulated in kdump line, since there's no use for it except to instruct systemd to load kdump; the only + reasonable case for removing it is to debug kdump itself. + + [Test Case] + 1) Deploy a Disco VM e.g. with uvt-kvm 2) Install the kdump-tools package 3) Run `kdump-config test`and check for the 'reset_devices' parameter: $ kdump-config test ... kexec command to be used: /sbin/kexec -p --command-line="BOOT_IMAGE=/boot/vmlinuz-4.15.0-45-generic root=LABEL=cloudimg-rootfs ro console=tty1 console=ttyS0 nr_cpus=1 systemd.unit=kdump-tools.service irqpoll nousb ata_piix.prefer_ms_hyperv=0" /var/lib/kdump/vmlinuz + Also, by changing the KDUMP_CMDLINE_APPEND we can see "systemd.unit + =kdump-tools.service" to be removed. + + [Regression Potential] - The regression potential is very low, since it doesn't need any changes in makedumpfile code and we're only adding a parameter on the crashkernel cmdline. - The fix will be tested with autopkgtests and normal kdump use-case scenarios. + + The regression potential is low, since it doesn't need any changes in + makedumpfile code and we're only adding a parameter on the crash kernel + command-line. The risks are related with bad behavior with the kernel + when using "reset_devices", like if the driver has bugs in this path. + It's considered safer to have the option (and this way prevent problems + for booting a unhealthy kernel with potential stuck DMAs in the devices) + than not having it. + + Regarding the other change, about the systemd service, it'll only affect + users the are debugging kdump itself and it has no known regression + potential. -- You received this bug notification because you are a member of Kernel Packages, which is subscribed to makedumpfile in Ubuntu. https://bugs.launchpad.net/bugs/1800566 Title: Make reset_devices parameter default for kdump and decouple kdump systemd service from the KDUMP_CMDLINE_APPEND Status in makedumpfile package in Ubuntu: Confirmed Status in makedumpfile source package in Trusty: Won't Fix Status in makedumpfile source package in Xenial: Confirmed Status in makedumpfile source package in Bionic: Confirmed Status in makedumpfile source package in Cosmic: Confirmed Status in makedumpfile source package in Disco: Confirmed Status in makedumpfile source package in Eoan: Confirmed Bug description: [Impact] * Kdump does not configure by default the crash kernel to perform a device reset by default, by passing the "reset_devices" parameter. Also, the systemd service "kdump-tools-dump" is tightly-coupled with KDUMP_CMDLINE_APPEND and it shouldn't, to prevent user confusion. * Kernel has the "reset_devices" parameter that drivers can opt-in, and perform special activity in case this parameter is parsed from command-line. For example, in kdump kernels it hints the drivers that they are booting from a non-healthy condition and needs to issue some form of reset to the adapter, like clearing DMA mapping in their firmware for example. Users currently (kernel v5.2) are: aacraid, hpsa,
[Kernel-packages] [Bug 1800566] Re: Make reset_devices parameter default for kdump and decouple kdump systemd service from the KDUMP_CMDLINE_APPEND
** Summary changed: - Make the reset_devices parameter default for kdump kernels + Make reset_devices parameter default for kdump and decouple kdump systemd service from the KDUMP_CMDLINE_APPEND -- You received this bug notification because you are a member of Kernel Packages, which is subscribed to makedumpfile in Ubuntu. https://bugs.launchpad.net/bugs/1800566 Title: Make reset_devices parameter default for kdump and decouple kdump systemd service from the KDUMP_CMDLINE_APPEND Status in makedumpfile package in Ubuntu: Confirmed Status in makedumpfile source package in Trusty: Won't Fix Status in makedumpfile source package in Xenial: Confirmed Status in makedumpfile source package in Bionic: Confirmed Status in makedumpfile source package in Cosmic: Confirmed Status in makedumpfile source package in Disco: Confirmed Status in makedumpfile source package in Eoan: Confirmed Bug description: [Impact] Crash kernels do not advise some subsystems to perform a reset by default. [Description] Kernel has the "reset_devices" parameter that drivers can opt-in, and perform special activity in case this parameter is parsed from command-line. For example, in kdump kernels it hints the drivers that they (maybe) are booting from a non-healthy condition and needs to issue some reset to the adapter. Users currently (kernel v4.19) are: hpsa, ipr, megaraid_sas, mpt3sas, smartpqi, xenbus. This should be enabled by default in the kdump config file to be added in the kdump kernel command-line for all versions. [Test Case] 1) Deploy a Disco VM e.g. with uvt-kvm 2) Install the kdump-tools package 3) Run `kdump-config test`and check for the 'reset_devices' parameter: $ kdump-config test ... kexec command to be used: /sbin/kexec -p --command-line="BOOT_IMAGE=/boot/vmlinuz-4.15.0-45-generic root=LABEL=cloudimg-rootfs ro console=tty1 console=ttyS0 nr_cpus=1 systemd.unit=kdump-tools.service irqpoll nousb ata_piix.prefer_ms_hyperv=0" /var/lib/kdump/vmlinuz [Regression Potential] The regression potential is very low, since it doesn't need any changes in makedumpfile code and we're only adding a parameter on the crashkernel cmdline. The fix will be tested with autopkgtests and normal kdump use-case scenarios. To manage notifications about this bug go to: https://bugs.launchpad.net/ubuntu/+source/makedumpfile/+bug/1800566/+subscriptions -- Mailing list: https://launchpad.net/~kernel-packages Post to : kernel-packages@lists.launchpad.net Unsubscribe : https://launchpad.net/~kernel-packages More help : https://help.launchpad.net/ListHelp
