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BAYES_HAM(-3.00)[100.00%]; NEURAL_HAM_LONG(-1.00)[-1.000]; NEURAL_HAM_SHORT(-0.16)[-0.785]; MIME_GOOD(-0.10)[text/plain]; ARC_NA(0.00)[]; MISSING_XM_UA(0.00)[]; FROM_HAS_DN(0.00)[]; MIME_TRACE(0.00)[0:+]; RCVD_COUNT_ZERO(0.00)[0]; RCPT_COUNT_SEVEN(0.00)[11]; MID_RHS_MATCH_FROMTLD(0.00)[]; DKIM_SIGNED(0.00)[suse.cz:s=susede2_rsa,suse.cz:s=susede2_ed25519]; FROM_EQ_ENVFROM(0.00)[]; TO_DN_SOME(0.00)[]; TO_MATCH_ENVRCPT_ALL(0.00)[]; FUZZY_BLOCKED(0.00)[rspamd.com]; DBL_BLOCKED_OPENRESOLVER(0.00)[suse.cz:email,localhost:helo] X-Spam-Flag: NO X-Spam-Level: Content-Transfer-Encoding: quoted-printable Content-Type: text/plain; charset="utf-8" Describe the new crashkernel ",cma" suffix in Documentation/ --- Documentation/admin-guide/kdump/kdump.rst | 19 +++++++++++++++++-- .../admin-guide/kernel-parameters.txt | 14 ++++++++++++++ 2 files changed, 31 insertions(+), 2 deletions(-) diff --git a/Documentation/admin-guide/kdump/kdump.rst b/Documentation/admi= n-guide/kdump/kdump.rst index 5376890adbeb..3f7ff301c604 100644 --- a/Documentation/admin-guide/kdump/kdump.rst +++ b/Documentation/admin-guide/kdump/kdump.rst @@ -213,8 +213,7 @@ Dump-capture kernel config options (Arch Dependent, i38= 6 and x86_64) kernel. =20 Otherwise it should be the start of memory region reserved for - second kernel using boot parameter "crashkernel=3DY@X". Here X is - start of memory region reserved for dump-capture kernel. + second kernel using boot parameter "crashkernel=3DY@X". Here X is start= of memory region reserved for dump-capture kernel. Generally X is 16MB (0x1000000). So you can set CONFIG_PHYSICAL_START=3D0x1000000 =20 @@ -315,6 +314,22 @@ crashkernel syntax =20 crashkernel=3D0,low =20 +4) crashkernel=3Dsize,cma + + Reserves additional memory from CMA. A standard crashkernel reservation= , as + described above, is still needed, but can be just big enough to hold the + kernel and initrd. All the memory the crash kernel needs for its runtim= e and + for running the kdump userspace processes can be provided by this CMA + reservation, re-using memory available to the production system's users= pace. + Because of this, the CMA reservation should not be used if kdump is con= figured + to dump userspace memory - the re-used memory ranges won't be in the vm= core. + + This option increases the risk of a kdump failure: DMA transfers config= ured + by the first kernel may end up corrupting the second kernel's memory. T= his + reservation method is intended for systems that can't afford to sacrifi= ce + enough memory for standard crashkernel reservation and where less relia= ble + kdump is preferrable to no kdump at all. + Boot into System Kernel ----------------------- 1) Update the boot loader (such as grub, yaboot, or lilo) configuration diff --git a/Documentation/admin-guide/kernel-parameters.txt b/Documentatio= n/admin-guide/kernel-parameters.txt index fb8752b42ec8..ea4d53435515 100644 --- a/Documentation/admin-guide/kernel-parameters.txt +++ b/Documentation/admin-guide/kernel-parameters.txt @@ -987,6 +987,20 @@ 0: to disable low allocation. It will be ignored when crashkernel=3DX,high is not used or memory reserved is below 4G. + crashkernel=3Dsize[KMG],cma + [KNL, X86] Reserve additional crash kernel memory from CMA. + This reservation is usable by the first system's userspace, + so this should not be used if dumping of userspace + memory is intended. A standard crashkernel reservation, + as described above, is still needed to hold the crash + kernel and initrd. + This option increases the risk of a kdump failure: DMA + transfers configured by the first kernel may end up + corrupting the second kernel's memory. This reservation + method is intended for systems that can't afford to + sacrifice enough memory for standard crashkernel + reservation and where less reliable kdump is preferrable=20 + to no kdump at all. =20 cryptomgr.notests [KNL] Disable crypto self-tests --=20 Jiri Bohac SUSE Labs, Prague, Czechia