kernel.git/arch/x86/include/asm/set_memory.h, branch linux-6.10.y

x86/tdx: Convert shared memory back to private on kexec

2024-10-04T14:33:44Z

[ Upstream commit 859e63b789d6b17b3c64e51a0aabdc58752a0254 ] TDX guests allocate shared buffers to perform I/O. It is done by allocating pages normally from the buddy allocator and converting them to shared with set_memory_decrypted(). The second, kexec-ed kernel has no idea what memory is converted this way. It only sees E820_TYPE_RAM. Accessing shared memory via private mapping is fatal. It leads to unrecoverable TD exit. On kexec, walk direct mapping and convert all shared memory back to private. It makes all RAM private again and second kernel may use it normally. The conversion occurs in two steps: stopping new conversions and unsharing all memory. In the case of normal kexec, the stopping of conversions takes place while scheduling is still functioning. This allows for waiting until any ongoing conversions are finished. The second step is carried out when all CPUs except one are inactive and interrupts are disabled. This prevents any conflicts with code that may access shared memory. Signed-off-by: Kirill A. Shutemov Signed-off-by: Borislav Petkov (AMD) Reviewed-by: Rick Edgecombe Reviewed-by: Kai Huang Tested-by: Tao Liu Link: https://lore.kernel.org/r/20240614095904.1345461-12-kirill.shutemov@linux.intel.com Stable-dep-of: d4fc4d014715 ("x86/tdx: Fix "in-kernel MMIO" check") Signed-off-by: Sasha Levin

x86/mm: Regularize set_memory_p() parameters and make non-static

2024-03-01T08:31:41Z

set_memory_p() is currently static. It has parameters that don't match set_memory_p() under arch/powerpc and that aren't congruent with the other set_memory_* functions. There's no good reason for the difference. Fix this by making the parameters consistent, and update the one existing call site. Make the function non-static and add it to include/asm/set_memory.h so that it is completely parallel to set_memory_np() and is usable in other modules. No functional change. Signed-off-by: Michael Kelley Reviewed-by: Rick Edgecombe Acked-by: Kirill A. Shutemov Link: https://lore.kernel.org/r/20240116022008.1023398-3-mhklinux@outlook.com Signed-off-by: Wei Liu Message-ID: <20240116022008.1023398-3-mhklinux@outlook.com>

x86/mm: Implement native set_memory_rox()

2022-12-15T18:37:27Z

Provide a native implementation of set_memory_rox(), avoiding the double set_memory_ro();set_memory_x(); calls. Suggested-by: Linus Torvalds Signed-off-by: Peter Zijlstra (Intel)

x86/mce: relocate set{clear}_mce_nospec() functions

2022-05-16T18:46:44Z

Relocate the twin mce functions to arch/x86/mm/pat/set_memory.c file where they belong. While at it, fixup a function name in a comment. Reviewed-by: Christoph Hellwig Reviewed-by: Dan Williams Signed-off-by: Jane Chu Acked-by: Borislav Petkov Cc: Stephen Rothwell [sfr: gate {set,clear}_mce_nospec() by CONFIG_X86_64] Link: https://lore.kernel.org/r/165272527328.90175.8336008202048685278.stgit@dwillia2-desk3.amr.corp.intel.com Signed-off-by: Dan Williams

Merge tag 'x86_cleanups_for_v5.18_rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip

2022-03-21T18:49:16Z

Pull x86 cleanups from Borislav Petkov: - Remove a misleading message and an unused function * tag 'x86_cleanups_for_v5.18_rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip: x86/nmi: Remove the 'strange power saving mode' hint from unknown NMI handler x86/pat: Remove the unused set_pages_array_wt() function

x86/mm/cpa: Generalize __set_memory_enc_pgtable()

2022-02-23T18:14:29Z

The kernel provides infrastructure to set or clear the encryption mask from the pages for AMD SEV, but TDX requires few tweaks. - TDX and SEV have different requirements to the cache and TLB flushing. - TDX has own routine to notify VMM about page encryption status change. Modify __set_memory_enc_pgtable() and make it flexible enough to cover both AMD SEV and Intel TDX. The AMD-specific behavior is isolated in the callbacks under x86_platform.guest. TDX will provide own version of said callbacks. [ bp: Beat into submission. ] Signed-off-by: Brijesh Singh Signed-off-by: Borislav Petkov Acked-by: Kirill A. Shutemov Link: https://lore.kernel.org/r/20220223043528.2093214-1-brijesh.singh@amd.com

x86/pat: Remove the unused set_pages_array_wt() function

2022-02-23T12:34:08Z

Commit 623dffb2a2e0 ("x86/mm/pat: Add set_memory_wt() for Write-Through type") added it but there were no users. [ bp: Add a commit message. ] Signed-off-by: Christoph Hellwig Signed-off-by: Borislav Petkov Link: https://lore.kernel.org/r/20220223072852.616143-1-hch@lst.de

x86/sgx: Hook arch_memory_failure() into mainline code

2021-11-15T19:13:16Z

Add a call inside memory_failure() to call the arch specific code to check if the address is an SGX EPC page and handle it. Note the SGX EPC pages do not have a "struct page" entry, so the hook goes in at the same point as the device mapping hook. Pull the call to acquire the mutex earlier so the SGX errors are also protected. Make set_mce_nospec() skip SGX pages when trying to adjust the 1:1 map. Signed-off-by: Tony Luck Signed-off-by: Dave Hansen Reviewed-by: Jarkko Sakkinen Reviewed-by: Naoya Horiguchi Tested-by: Reinette Chatre Link: https://lkml.kernel.org/r/20211026220050.697075-6-tony.luck@intel.com

mm: x86: Invoke hypercall when page encryption status is changed

2021-11-11T12:37:24Z

Invoke a hypercall when a memory region is changed from encrypted -> decrypted and vice versa. Hypervisor needs to know the page encryption status during the guest migration. Cc: Thomas Gleixner Cc: Ingo Molnar Cc: "H. Peter Anvin" Cc: Paolo Bonzini Cc: Joerg Roedel Cc: Borislav Petkov Cc: Tom Lendacky Cc: x86@kernel.org Cc: kvm@vger.kernel.org Cc: linux-kernel@vger.kernel.org Reviewed-by: Steve Rutherford Reviewed-by: Venu Busireddy Signed-off-by: Brijesh Singh Signed-off-by: Ashish Kalra Reviewed-by: Borislav Petkov Message-Id: <0a237d5bb08793916c7790a3e653a2cbe7485761.1629726117.git.ashish.kalra@amd.com> Signed-off-by: Paolo Bonzini

x86: Fix various typos in comments, take #2

2021-03-21T22:50:28Z

Fix another ~42 single-word typos in arch/x86/ code comments, missed a few in the first pass, in particular in .S files. Signed-off-by: Ingo Molnar Cc: Borislav Petkov Cc: Thomas Gleixner Cc: Peter Zijlstra Cc: Paolo Bonzini Cc: Bjorn Helgaas Cc: linux-kernel@vger.kernel.org