kernel.git/arch/x86/kernel/irqinit.c, branch linux-rolling-stable

x86/fred: Install system vector handlers even if FRED isn't fully enabled

2025-08-18T12:23:08Z

Install the system vector IRQ handlers for FRED even if FRED isn't fully enabled in hardware. This will allow KVM to use the FRED IRQ path even on non-FRED hardware, which in turn will eliminate a non-CFI indirect CALL (KVM currently invokes the IRQ handler via an IDT lookup on the vector). [sean: extract from diff, drop stub, write changelog] Signed-off-by: Sean Christopherson Signed-off-by: Peter Zijlstra (Intel) Link: https://lkml.kernel.org/r/20250714103441.121251108@infradead.org

x86/fred: Invoke FRED initialization code to enable FRED

2024-01-31T21:03:36Z

Let cpu_init_exception_handling() call cpu_init_fred_exceptions() to initialize FRED. However if FRED is unavailable or disabled, it falls back to set up TSS IST and initialize IDT. Co-developed-by: Xin Li Signed-off-by: H. Peter Anvin (Intel) Signed-off-by: Xin Li Signed-off-by: Thomas Gleixner Signed-off-by: Borislav Petkov (AMD) Tested-by: Shan Kang Link: https://lore.kernel.org/r/20231205105030.8698-36-xin3.li@intel.com

x86/i8259: Mark legacy PIC interrupts with IRQ_LEVEL

2023-01-16T16:24:56Z

Baoquan reported that after triggering a crash the subsequent crash-kernel fails to boot about half of the time. It triggers a NULL pointer dereference in the periodic tick code. This happens because the legacy timer interrupt (IRQ0) is resent in software which happens in soft interrupt (tasklet) context. In this context get_irq_regs() returns NULL which leads to the NULL pointer dereference. The reason for the resend is a spurious APIC interrupt on the IRQ0 vector which is captured and leads to a resend when the legacy timer interrupt is enabled. This is wrong because the legacy PIC interrupts are level triggered and therefore should never be resent in software, but nothing ever sets the IRQ_LEVEL flag on those interrupts, so the core code does not know about their trigger type. Ensure that IRQ_LEVEL is set when the legacy PCI interrupts are set up. Fixes: a4633adcdbc1 ("[PATCH] genirq: add genirq sw IRQ-retrigger") Reported-by: Baoquan He Signed-off-by: Thomas Gleixner Tested-by: Baoquan He Link: https://lore.kernel.org/r/87mt6rjrra.ffs@tglx

x86/headers: Remove APIC headers from

2020-08-06T14:13:09Z

The APIC headers are relatively complex and bring in additional header dependencies - while smp.h is a relatively simple header included from high level headers. Remove the dependency and add in the missing #include's in .c files where they gained it indirectly before. Signed-off-by: Ingo Molnar

mm: reorder includes after introduction of linux/pgtable.h

2020-06-09T16:39:13Z

The replacement of with made the include of the latter in the middle of asm includes. Fix this up with the aid of the below script and manual adjustments here and there. import sys import re if len(sys.argv) is not 3: print "USAGE: %s

" % (sys.argv[0]) sys.exit(1) hdr_to_move="#include " % sys.argv[2] moved = False in_hdrs = False with open(sys.argv[1], "r") as f: lines = f.readlines() for _line in lines: line = _line.rstrip(' ') if line == hdr_to_move: continue if line.startswith("#include Signed-off-by: Andrew Morton Cc: Arnd Bergmann Cc: Borislav Petkov Cc: Brian Cain Cc: Catalin Marinas Cc: Chris Zankel Cc: "David S. Miller" Cc: Geert Uytterhoeven Cc: Greentime Hu Cc: Greg Ungerer Cc: Guan Xuetao Cc: Guo Ren Cc: Heiko Carstens Cc: Helge Deller Cc: Ingo Molnar Cc: Ley Foon Tan Cc: Mark Salter Cc: Matthew Wilcox Cc: Matt Turner Cc: Max Filippov Cc: Michael Ellerman Cc: Michal Simek Cc: Nick Hu Cc: Paul Walmsley Cc: Richard Weinberger Cc: Rich Felker Cc: Russell King Cc: Stafford Horne Cc: Thomas Bogendoerfer Cc: Thomas Gleixner Cc: Tony Luck Cc: Vincent Chen Cc: Vineet Gupta Cc: Will Deacon Cc: Yoshinori Sato Link: http://lkml.kernel.org/r/20200514170327.31389-4-rppt@kernel.org Signed-off-by: Linus Torvalds

mm: introduce include/linux/pgtable.h

2020-06-09T16:39:13Z

The include/linux/pgtable.h is going to be the home of generic page table manipulation functions. Start with moving asm-generic/pgtable.h to include/linux/pgtable.h and make the latter include asm/pgtable.h. Signed-off-by: Mike Rapoport Signed-off-by: Andrew Morton Cc: Arnd Bergmann Cc: Borislav Petkov Cc: Brian Cain Cc: Catalin Marinas Cc: Chris Zankel Cc: "David S. Miller" Cc: Geert Uytterhoeven Cc: Greentime Hu Cc: Greg Ungerer Cc: Guan Xuetao Cc: Guo Ren Cc: Heiko Carstens Cc: Helge Deller Cc: Ingo Molnar Cc: Ley Foon Tan Cc: Mark Salter Cc: Matthew Wilcox Cc: Matt Turner Cc: Max Filippov Cc: Michael Ellerman Cc: Michal Simek Cc: Nick Hu Cc: Paul Walmsley Cc: Richard Weinberger Cc: Rich Felker Cc: Russell King Cc: Stafford Horne Cc: Thomas Bogendoerfer Cc: Thomas Gleixner Cc: Tony Luck Cc: Vincent Chen Cc: Vineet Gupta Cc: Will Deacon Cc: Yoshinori Sato Link: http://lkml.kernel.org/r/20200514170327.31389-3-rppt@kernel.org Signed-off-by: Linus Torvalds

x86: Replace setup_irq() by request_irq()

2020-03-21T14:15:47Z

request_irq() is preferred over setup_irq(). The early boot setup_irq() invocations happen either via 'init_IRQ()' or 'time_init()', while memory allocators are ready by 'mm_init()'. setup_irq() was required in old kernels when allocators were not ready by the time early interrupts were initialized. Hence replace setup_irq() by request_irq(). [ tglx: Use a local variable and get rid of the line break. Tweak the comment a bit ] Signed-off-by: afzal mohammed Signed-off-by: Thomas Gleixner Link: https://lkml.kernel.org/r/17f85021f6877650a5b09e0212d88323e6a30fd0.1582471508.git.afzal.mohd.ma@gmail.com

x86: Fix a handful of typos

2020-02-16T19:58:06Z

Fix a couple of typos in code comments. [ bp: While at it: s/IRQ's/IRQs/. ] Signed-off-by: Martin Molnar Signed-off-by: Borislav Petkov Reviewed-by: Randy Dunlap Link: https://lkml.kernel.org/r/0819a044-c360-44a4-f0b6-3f5bafe2d35c@gmail.com

x86/irq/32: Handle irq stack allocation failure proper

2019-04-17T13:31:42Z

irq_ctx_init() crashes hard on page allocation failures. While that's ok during early boot, it's just wrong in the CPU hotplug bringup code. Check the page allocation failure and return -ENOMEM and handle it at the call sites. On early boot the only way out is to BUG(), but on CPU hotplug there is no reason to crash, so just abort the operation. Rename the function to something more sensible while at it. Signed-off-by: Thomas Gleixner Signed-off-by: Borislav Petkov Cc: Alison Schofield Cc: Andrew Morton Cc: Andy Lutomirski Cc: Anshuman Khandual Cc: Boris Ostrovsky Cc: "H. Peter Anvin" Cc: Ingo Molnar Cc: Josh Poimboeuf Cc: Juergen Gross Cc: Konrad Rzeszutek Wilk Cc: Nicolai Stange Cc: Pu Wen Cc: Sean Christopherson Cc: Shaokun Zhang Cc: Stefano Stabellini Cc: Suravee Suthikulpanit Cc: x86-ml Cc: xen-devel@lists.xenproject.org Cc: Yazen Ghannam Cc: Yi Wang Cc: Zhenzhong Duan Link: https://lkml.kernel.org/r/20190414160146.089060584@linutronix.de

x86/irq/32: Invoke irq_ctx_init() from init_IRQ()

2019-04-17T13:30:12Z

irq_ctx_init() is invoked from native_init_IRQ() or from xen_init_IRQ() code. There is no reason to have this split. The interrupt stacks must be allocated no matter what. Invoke it from init_IRQ() before invoking the native or XEN init implementation. Signed-off-by: Thomas Gleixner Signed-off-by: Borislav Petkov Reviewed-by: Juergen Gross Cc: Andy Lutomirski Cc: Boris Ostrovsky Cc: "H. Peter Anvin" Cc: Ingo Molnar Cc: Josh Abraham Cc: Josh Poimboeuf Cc: Juergen Gross Cc: Mike Rapoport Cc: Nicolai Stange Cc: Sean Christopherson Cc: Stefano Stabellini Cc: Stephen Rothwell Cc: x86-ml Cc: xen-devel@lists.xenproject.org Link: https://lkml.kernel.org/r/20190414160146.001162606@linutronix.de