mirror of
https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git
synced 2026-09-22 09:34:56 +02:00
Alexey Kardashevskiy
b4abeccb8d
The __snp_alloc_firmware_pages() helper allocates pages in the firmware state (alloc + rmpupdate). In case of failed rmpupdate, it tries reclaiming pages with already changed state. This requires calling the PSP firmware and since there is sev_cmd_mutex to guard such calls, the helper takes a "locked" parameter so specify if the lock needs to be held. Most calls happen from snp_alloc_firmware_page() which executes without the lock. However commit24512afa43("crypto: ccp: Handle the legacy TMR allocation when SNP is enabled") switched sev_fw_alloc() from alloc_pages() (which does not call the PSP) to __snp_alloc_firmware_pages() (which does) but did not account for the fact that sev_fw_alloc() is called from __sev_platform_init_locked() (via __sev_platform_init_handle_tmr()) and executes with the lock held. Add a "locked" parameter to __snp_alloc_firmware_pages(). Make sev_fw_alloc() use the new parameter to prevent potential deadlock in rmp_mark_pages_firmware() if rmpupdate() failed. Fixes:24512afa43("crypto: ccp: Handle the legacy TMR allocation when SNP is enabled") Signed-off-by: Alexey Kardashevskiy <aik@amd.com> Reviewed-by: Tom Lendacky <thomas.lendacky@amd.com> Reviewed-by: Pratik R. Sampat <prsampat@amd.com> Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>
Linux kernel
============
There are several guides for kernel developers and users. These guides can
be rendered in a number of formats, like HTML and PDF. Please read
Documentation/admin-guide/README.rst first.
In order to build the documentation, use ``make htmldocs`` or
``make pdfdocs``. The formatted documentation can also be read online at:
https://www.kernel.org/doc/html/latest/
There are various text files in the Documentation/ subdirectory,
several of them using the reStructuredText markup notation.
Please read the Documentation/process/changes.rst file, as it contains the
requirements for building and running the kernel, and information about
the problems which may result by upgrading your kernel.